TRANSACTIONS 


OF  THE 


AMERICAN  INSTITUTE  OF  MINING 
AND  METALLURGICAL  ENGINEERS 

(INCOHPO  RATED) 
WITH  WHICH  IS  CONSOLIDATED  THE 

AMERICAN  INSTITUTE  OP  METALS 

.VOL.  LXV 


CONTAINING  PAPERS  AND  DISCUSSIONS  ON  PETROLEUM  AND  GAS 


NEW    YORK,   N.  Y. 
PUBLISHED  BY   THE  INSTITUTE 

AT  THE  OFFICE  OF  THE  SECRETARY 
29  WEST  39TH  STREET 

1921 


COPYRIGHT,  1921,  BY  THE 

AMERICAN  INSTITUTE  OF  MINING  AND  METALLURGICAL  ENGINEERS 
[INCORPORATED]  . 


FBKNH      TO.K      FA 


Bancroft  Library 

**&+  PREFACE 


In  this  volume  are  the  papers  and  discussions  on  Petroleum  and 
Gas  that  were  presented  at  the  Chicago  meeting,  September,  1919,  the 
Lake  Superior  and  St.  Louis  meetings,  August  and  September,  1920, 
the  New  York  meetings  of  1920  and  1921,  and  the  Wilkes-Barre  meeting, 
September,  1921;  also  proceedings  of  the  St.  Louis  meeting. 


CM 
0> 


VI  CONTENTS 

PAGE 

Variation  in  Decline  Curves  of  Various  Oil  Pools.     By  R.  H.  JOHNSON  (With 

Discussion) 365 

Application  of  Taxation  Regulations  to  Oil  and  Gas  Properties.     By  THOMAS  Cox 

(With  Discussion) 374 

Valuation  Factors  in  Casing-head  Gas  Industry.  By  O.  U.  BRADLEY  (With  Dis- 
cussion)  395 

Modified  Oil-well  Depletion  Curves.  By  ARTHUR  KNAPP  (With  Discussion) ...  405 
Barrel-day  Values.  By  G.  H.  ALVEY  and  A.  W.  FOSTER  (With  Discussion)  .  .  412 
Isostatic  Adjustments  on  a  Minor  Scale,  in  their  Relation  to  Oil  Domes.  By  M. 

A.LBERTSON 418 

Anthony  F.  Lucas — Biographical  Notice.  By  H.  B.  GOODRICH 421 

Rock  Classification  from  the  Oil-driller's  Standpoint.  By  ARTHUR  KNAPP.  .  .  .  424 
Investigations  Concerning  Oil-water  Emulsion.  By  A.  W.  McCoY,  H.  R. 

SHIDEL  and  E.  A.  TRACER  (With  Discussion) 430 

Drilling  and  Production  Technique  in  the  Baku  Oil  Fields.  By  ARTHUR  KNAPP 

(With  Discussion) 459 

Determination  of  Pore  Space  of  Oil  and  Gas  Sands.  By  A.  F.  MELCHER  (With 

Discussion) 469 

Water  Displacement  in  Oil  and  Gas  Sands.  By  R.  H.  JOHNSON  (With  Dis- 
cussion)   498 

Composition  of  Petroleum  and  its  Relation  to  Industrial  Use.  By  C.  F.  MABERY 

(With  Discussion) 505 

Carbon  Ratios  of  Coals  in  West  Virginia  Oil  Fields.  By  DAVID  B.  REGER  (With 

Discussion) 522 

General  Notes  on  the  Production,  Marine  Transportation  and  Taxation  of 

Mexican  Petroleums.  By  V.  R.  GARFIAS 528 

Efficiency  in  Use  of  Oil  as  Fuel.  By  W.  N.  BEST  (With  Discussion) 568 


PROCEEDINGS    OF   THE    ST.    LOUIS   MEETING  vii 

Petroleum  and  Gas  Meeting  at  St.  Louis 

A  SPECIAL  meeting  arranged  by  the  Petroleum  and  Gas  Committee 
of  the  American  Institute  of  Mining  and  Metallurgical  Engineers  was 
held  on  Tuesday  and  Wednesday,  Sept.  21  and  22,  1920,  in  the  Assembly 
Room  of  the  American  Annex  Hotel,  St.  Louis,  Mo.  Those  in  attendance 
were  guests  of  the  St.  Louis  Local  Section. 

Preceding  the  first  session  on  Tuesday  morning,  the  members  and 
guests  were  registered  and  presented  with  the  usual  Institute  badges. 
The  morning  session  was  opened  at  10:30  by  Ralph  Arnold  of  Los  Angeles, 
Calif.,  chairman  of  the  Petroleum  and  Gas  Committee.  In  his  opening 
remarks,  he  suggested  that  the  petroleum  section  specialize  more  and 
more  on  the  technical  problems  of  the  oil  industry  and  that  an  effort  be 
made  to  enlarge  the  membership  of  the  Institute  among  the  technical 
men  of  the  industry.  The  following  program  was  presented: 

Oil  Fields  of  Russia,  by  A.  Beeby  Thompson  and.T.  G.  Madgwick,  of  London, 
England.  Presented  by  H.  A.  Wheeler;  discussed  by  Arthur  Knapp  and  R.  Van  A. 
Mills. 

This  most  comprehensive  paper  was  one  of  what  is  hoped  to  be  a 
series  to  be  presented  by  some  of  our  foreign  members.  It  is  by  far  the 
best  description  in  English  of  the  world-famous  Baku  and  other  fields  of 
Russia. 

Extended  Life  of  Wells  Due  to  Rise  in  Price  of  Oil,  by  WiUard  W.  Cutler,  Jr.,  of 
Chevy  Chase,  Md.  Presented  by  the  author;  discussed  by  J.  L.  Darnell. 

This  paper  brought  graphically  before  the  audience  the  fact  that  the 
economic  life  of  a  well  lengthens  as  the  price  of  oil  goes  up. 

Urgency  for  Deeper  Drilling  on  the  Gulf  Coast,  by  A.  F.  Lucas,  of  Washington, 
D.  C.  Presented  by  Mowry  Bates;  discussed  by  David  White,  W.  E.  Pratt,  Mo  wry 
Bates,  R.  Van  A.  Mills,  J.  L.  Henning,  Arthur  Knapp  and  E.  DeGolyer. 

.  This  paper  opened  up  the  always  interesting  subject  of  salt  domes  on 
the  Gulf  Coast  and  the  possibility  of  the  occurrence  of  oil  at  great  depth 
in  these  structures. 

Petroleum  Industry  of  Trinidad,  by  George  A.  Macready,  of  Los  Angeles,  Calif- 
Presented  by  R.  A.  Conkling;  discussed  by  Arthur  Knapp,  R.  A.  Conkling,  E.  De- 
Golyer, Ralph  Arnold  and  R.  Van  A.  Mills. 

Oil  Shales  and  Petroleum  Prospects  in  Brazil,  by  H.  E.  Williams,  of  Rio  de  Janeiro, 
Brazil.  Presented  by  J.  Elmer  Thomas;  discussed  by  David  White,  Mowry  Bates, 
B.  O.  Mahaffy,  J.  Elmer  Thomas  and  Ralph  Arnold. 

The  latter  paper  brought  out  the  point  that  there  are  possibilities  of 
developing  oil  from  oil  shales,  and  in  addition  that  there  are  certain 
localities  along  the  eastern  flanks  of  the  Andes  in  Brazil  that  may 
eventually  yield  commercial  quantities  of  oil. 


Viii  PROCEEDINGS   OF  THE   ST.   LOUIS   MEETING 

TUESDAY  AFTERNOON  SESSION 

The  afternoon  session  was  opened  at  2.30  and  was  presided  over  by 
Vice-chairman  E.  DeGolyer.  The  following  papers  were  given: 

Determination  of  Pore  Space  in  Oil  and  Gas  Sands,  by  A.  F.  Melcher  of  Washing- 
ton, D.  C.  Presented  by  W.  E.  Pratt;  discussed  by  R.  Van  A.  Mills,  Walter  M. 
Small,  W.  W.  Cutler,  Jr.  and  David  White. 

This  paper  brought  out  the  point  that  there  are  other  determining 
factors  affecting  the  oil  saturation  of  rocks  than  the  size  and  shape  of 
the  grains. 

Application  of  Taxation  Regulations  to  Oil  and  Gas  Properties,  by  Thomas  Cox, 
of  Oakland,  Calif.  Presented  by  E.  B.  Hopkins;  discussed  by  Ralph  Arnold,  J.  L. 
Henning  and  W.  E.  Pratt. 

Oil  Possibilities  of  Northern  Alabama,  by  D.  M.  Semmes,  of  University,  Ala. 
Presented  by  Walter  M.  Small;  discussed  by  David  White  and  Mowry  Bates. 

Efficiency  in  Use  of  Oil  and  Gas  as  Fuel,  by  W.  N.  Best,  of  New  York.  Presented 
by  James  H.  Hance;  discussed  by  S.  O.  Andros,  H.  P.  Mueller,  J.  L.  Henning,  I.  N. 
Knapp,  and  C.  H.  Matthews. 

Industrial  Representation  in  the  Standard  Oil  Co.  of  N.  J.,  by  C.  J.  Hicks,  New 
York.  Presented  by  John  L.  Henning;  discussed  by  Ralph  Arnold,  W.  E.  Pratt,  and 
Mr.  Trowbridge. 

Valuation  Factors  in  Casinghead  Gas  Industry,  by  O.  U.  Bradley,  Muskogee, 
Okla.  Presented  by  W.  B.  Wilson;  discussed  by  W.  E.  Pratt,  E.  DeGolyer,  J.  L. 
Henning,  W.  M.  Small  and  Mr.  Reeves. 

Nature  of  Coal,  by  J.  E.  Hackford  of  London,  England.  Presented  by  David 
White;  discussed  by  Ralph  Arnold,  David  White,  W.  E.  Pratt  and  E.  DeGolyer. 

In  the  evening  an  informal  smoker  was  given  to  the  visiting  members 
and  guests  at  the  American  Annex  Hotel.  Moving  pictures  were  shown ; 
some  short  speeches  were  given  and  suitable  refreshments  provided. 
The  evening  was  greatly  enjoyed  by  those  present. 

WEDNESDAY  SESSIONS 

The  Wednesday  morning  session  was  called  to  order  at  10  o'clock 
by  Ralph  Arnold,  who  presided.  The  following  program  was  presented: 

Analysis  of  Oil-field  Water  Problems,  by  A.  W.  Ambrose,  Bartlesville,  Okla. 
Presented  by  C.  E.  Beecher;  discussed  by  R.  A.  Conkling,  R.  Van  A.  Mills,  E.  De- 
Golyer, Mr.  Reilly  and  Mr.  Compton. 

Contribution  of  Oil  Geology  to  Success  in  Drilling,  by  F.  G.  Clapp,  of  New  York. 
Presented  by  W.  E.  Wrather;  discussed  by  E.  DeGolyer. 

Ultimate  Source  of  Kentucky  Crudes,  by  W.  R.  Jillson,  of  Frankfort,  Ky.  Pre- 
sented by  title,  as  manuscript  was  not  received  in  time  for  preparing  abstract. 

Oil-field  Brines,  by  C.  W.  Washburne  of  New  York.  Presented  by  Walter  M. 
Small;  discussed  by  R.  Van  A.  Mills,  E.  DeGolyer,  W.  M.  Small,  R.  A.  Conkling, 
Mr.  Reilly,  W.  E.  Pratt  and  W.  E.  Wrather. 

The  last  paper  brought  out  further  discussion  regarding  the  theories 
of  origin  of  salt  domes. 


PROCEEDINGS    OF   THE    ST.    LOUIS   MEETING  IX 

The  above  list  completed  the  formal  papers.  Following  the  formal 
meeting  the  ensuing  papers  were  presented  without  discussion: 

Gulf  Cretaceous  Oil  Fields,  by  Julius  Fohs.    Presented  by  the  author. 
Oil  Resources  of  Illinois,  by  Mr.  Mylius,  of  Urbana,  111.     Presented  by  the  author. 
Influence  of  Faults  in  the  Illinois  Fields,  by  H.  A.  Wheeler,  of  St.  Louis,  Mo. 
Presented  by  the  author. 

Prior  to  the  adjournment  of  the  meeting  a  resolution  was  passed 
extending  the  thanks  of  those  present  to  the  St.  Louis  Local  Section  for 
its  hospitality  and  for  the  courtesies  extended  during  the  meeting,  with  a 
special  vote  of  thanks  to  Dr.  H.  A.  Wheeler  for  his  untiring  efforts  in 
making  the  meeting  a  success. 

The  afternoon  of  the  twenty-second  was  spent  in  a  trip  to  interesting 
points  about  St.  Louis,  in  automobiles  provided  by  the  St.  Louis  Section. 


PAPERS 


VOL.    LXV. 1. 


4  PETROLEUM   RESOURCES    OF   GREAT  BRITAIN 

they  could  not  remain  in  the  government  if  such  legislation  was  passed  as 
a  government  measure.  The  compromise  reached  was  that  a  bill  should 
be  passed  declaring  that  no  one  could  sink  a  test  well  for  oil  or  gas  in 
Great  Britain  without  a  license  from  the  government,  and  the  question 
of  royalty  and  ownership  would  be  dealt  with  after  the  war.  The  govern- 
ment gave  an  undertaking  to  Parliament  that  it  would  not  recognize  the 
payment  of  royalties  on  oil  until  Parliament  had  acted.  This  legisla- 
tion was  passed  in  October,  1918.  The  government  then  took  the  land 
necessary  for  nine  well  sites  (seven  in  Derbyshire  and  two  in  Stafford- 
shire) under  the  powers  given  it  by  the  Defence  of  the  Realm  Acts. 
This  gave  the  right  of  occupancy,  but  not  of  ownership.  Later,  two 
additional  sites  were  taken  in  Scotland;  as  one  of  these  was  taken  after 
the  signing  of  the  armistice  the  validity  of  the  action  is  now  the  subject 
of  a  lawsuit.  The  present  condition  is,  therefore,  that  while  the  govern- 
ment may  still  legally,  for  the  time  being,  have  the  power  to  take  sites 
under  the  Defence  of  the  Realm  Acts,  it  cannot  justify  the  expediency  of 
so  doing;  it  cannot  acquire  such  sites  by  agreement,  because  this  would 
involve  the  payment  of  a  royalty  to  the  landlord,  or  the  recognition  of  his 
ownership  of  the  oil,  and  it  cannot  grant  a  license  to  anyone  else  because 
this  also  would  involve  the  same  recognition  indirectly. 

The  first  well  sunk  by  the  government  found  commercial  oil,  and  while 
it  would  have  been  relatively  easy  to  pass  legislation  giving  the  ownership 
of  the  oil  to  the  government  when  the  majority  of  the  landlords  had  no 
belief  in  its  existence,  the  laborites  and  extreme  radicals  have  now  been 
furnished  with  the  politically  effective  argument  that  the  oil  was  found 
with  government  money.  Even  the  utilization  of  the  oil  found  in  the 
test  wells,  which  will  be  limited  to  the  ones  already  started,  is  subject  to 
the  serious  handicap  that  whenever  the  government  starts  to  remove  the 
oil  from  the  tankage  at  the  well  site  the  landlord  will  immediately  start 
injunction  proceedings. 

FUTURE  COMMERCIAL  PROSPECTS 

In  the  center  of  England  the  Mountain  limestone  (Mississippian)  is 
exposed  along  the  axis  of  the  Pennine  fold.  Like  the  similar  carbonif- 
erous limestones  in  Kentucky  and  Missouri,  it  is  cut  by  spar  and  lead 
veins,  but  unlike  these,  it  contains  numerous  important  seepages  of 
petroleum.  The  upper  100  to  150  ft.  (30  to  45  m.)  of  this  limestone  is 
dolomitic.  Overlying  the  Mountain  limestone  are  the  Yoredale  shales 
and  sandstones,  which  in  the  important  area  to  the  east  have  a  thickness 
of  from  400  to  700  ft.  (121  to  213  m.)  and  in  the  area  to  the  west,  2000  to 
2500  ft.  The  Yoredale  shales  are  followed  by  the  Millstone  grits  series 
of  shales  and  important  porous  sandstones  with  a  total  thickness  on 
the  east  of  700  to  900  ft.,  and  on  the  west  of  about  300  ft.;  these,  in  turn, 


A.    C.    VEATCH  5 

are  succeeded  by  the  productive  coal  measures.  On  each  side  of  the 
main  Pennine  fold,  subsidiary  folds  produce  a  whole  series  of  local  domes, 
anticlines,  and  terraces  in  the  regions  where  the  limestone  is  overlaid  by 
the  Yoredale  and  succeeding  rocks.  There  is  considerable  faulting,  but 
the  character  of  the  oil  produced  in  the  limestone  is  such  that,  while  it  is 
of  a  paraffin  base,  it  oxidizes  even  more  rapidly  than  an  asphaltic  oil. 
There  are  no  surface  exudations  of  oil  of  importance  on  either  side  of  the 
main  limestone  mass,  but  for  the  last  century  the  coal  mines  on  either 
side  have  encountered  important  flows  of  oil  on  fault  planes. 

The  discovery  well  is  located  on  a  faulted  dome  at  Hardstoft,  Derby- 
shire, where  none  of  the  coal  mines  had  found  oil  in  the  fault  planes. 
It  started  in  the  coal  measures,  found  wax  in  drilling  through  a  fault,  a 
commercial  supply  of  gas  in  the  Millstone  grits,  which  was  muddied 
off,  and  oil  in  the  top  of  the  limestone  at  a  depth  of  3078  ft.  (938  m.). 
This  well  has  been  flowing  at  the  rate  of  12  bbl.  per  day  since  June  of 
this  year,  and  is  estimated  to  have  a  pumping  capacity  in  excess  of  50  bbl. 
The  well  has  not  been  "shot;"  first,  because  the  transportation  of 
nitroglycerine  on  the  roads  of  England  is  not  permitted,  and,  second, 
because  the  war  emergency  being  over,  the  question  of  the  ownership 
of  the  oil  has  become  acute,  and  when  the  present  tankage  is  filled  the 
removal  of  the  oil  will  undoubtedly  involve  a  legal  fight. 

Two  wells,  located  on  domes  south  of  Hardstoft,  both  started  in  the 
coal  measures,  penetrated  the  Millstone  grits  without  finding  gas  in 
any  considerable  quantities,  showed  a  little  oil  in  the  top  of  the  limestone, 
and  are  now  drilling  in  the  limestone,  where  they  have  encountered  a 
little  gas.  It  is  planned  to  " shoot"  these  wells  whenever  conditions 
permit.  Three  wells  on  different  structures  to  the  north  of  Hardstoft 
have  encountered  commercial  gas  in  the  Millstone  grits,  but  have  not 
yet  reached  the  limestone.  The  two  wells  which  have  been  started  on 
the  west  side  of  the  Pennine  axis  in  Staffordshire  have  not  yet  reached  a 
sufficient  depth  to  be  interesting.  The  area  in  the  center  of  England 
that  has  important  petroleum  possibilities  is  between  20,000  and  30,000 
square  miles. 

The  two  wells  that  are  being  drilled  in  Scotland  are  in  an  entirely 
different  category.  They  are  merely  " wildcat"  wells,  with  a  moderate 
chance  of  being  successful.  One  is  located  at  West  Calder,  on  a  dome  in 
the  oil-shale  fields,  16  mi.  southwest  of  Edinburgh,  and  the  other  on  a 
dome  at  Darcy,  10  mi.  southeast  of  Edinburgh — both  in  Edinburgh- 
shire.  They  both  start  in  what  is  considered  the  northern  equivalent 
of  the  lower  part  of  the  Mountain  limestone,  which  is  here  for  the  most 
part  the  oil-shale  series.  They  will  both  penetrate  between  2000  and 
2500  ft.  (609  and  761  m.)  important  untested  sandstones  underlying  the 
oil  shales,  and  are  expected  to  reach  the  old  red  sandstone  (Devonian)  at 
from  3300  to  4000  ft.  A  certain  amount  of  free  oil  and  wax  has  been 


6  PETROLEUM  RESOURCES  OP  GREAT  BRITAIN 

found  in  connection  with  the  shale  mining — sometimes  in  the  associated 
sandstones;  sometimes  on  the  faces  of  the  igneous  sills.  This  free  oil 
has  always  been  considered  as  due  to  destructive  distillation  of  the  shale 
by  heat  from  the  igneous  rocks,  but  Mr.  J.  E.  Hackford  finds  that  it  has 
many  things  which  distinguish  it  from  an  oil  that  could  be  produced  by 
the  destructive  distillation  of  the  shales,  and  reaches  the  conclusion  that 
it  has  come  from  below  after  the  igneous  rocks  had  cooled.  This,  taken 
in  connection  with  the  fact  that  the  Devonian  sandstones  show  some  oil 
in  the  north  of  Scotland  and  in  the  Orkneys,  has  led  to  the  location  of  the 
two  test  wells  in  Scotland. 

The  present  work  in  Great  Britain  had  its  inception  in  1914,  when  the 
outbreak  of  the  war  enabled  the  writer  and  his  associates  to  carry  out  a 
long  deferred  desire  to  see  just  what  the  numerous  indications  of  petro- 
leum in  Great  Britain  really  meant.  Thanks  to  the  great  mass  of  funda- 
mental geological  information  which  the  Geological  Survey  of  Great 
Britain  had  collected  and  published,  and  particularly  to  the  detail  work 
carried  out  in  certain  coal  fields,  it  was  possible  in  a  short  time  to 
present  to  Lord  Cowdray  the  conclusion  that  the  petroleum  possibilities 
of  the  Midlands  of  England  were  of  a  most  amazing  and  striking 
character.  Lord  Cowdray,  after  a  momentary  hesitation,  shared  our 
enthusiasm.  With  the  increase  of  the  submarine  menace,  he  offered  to 
place  the  services  of  his  firm  and  his  petroleum  staff  at  the  disposal  of 
the  nation,  free  of  cost,  for  carrying  this  work  forward  as  a  war  measure. 
This  was  a  gift  made  to  the  nation  without  any  commitment  of  any  kind 
on  the  part  of  the  British  Government  to  Lord  Cowdray. 

Special  mention  should  be  made  of  the  work  of  Mr.  Eugene  L.  Ickes, 
a  graduate  of  the  University  of  California  and  an  American  geologist 
of  marked  ability.  Mr.  Roderic  Crandall,  of  Stanford  University,  who 
was  in  charge  of  the  technical  administration  of  the  work,  and  Mr. 
Victor  L.  Conaghan,  drilling  superintendent,  who  was  very  kindly 
supplied  as  a  war  measure  by  the  United  States  Bureau  of  Mines. 

The  oil  from  the  Hardstoft  well  has  the  following  characteristics: 
Specific  gravity,  0.823;  sulfur,  0.26  per  cent.;  gasoline,  7.5  per  cent.; 
kerosene,  39.0  per  cent. ;  wax,  6.0  per  cent. ;  gas  oil,  20.0  per  cent. ;  lubri- 
cating oil,  30.0  per  cent.  The  oil  is  particularly  rich  in  very  high-grade 
lubricants. 

DISCUSSION 

CHESTER  W.  WASHBURNE,  New  York,  N.  Y.  (written  discussion). 
The  work  of  Mr.  Veatch  and  his  associates  in  directing  the  work  that 
promises  to  add  England  to  the  list  of  oil-producing  countries  indicates 
the  value  of  science,  as  well  as  their  ability  to  apply  it.  Englishmen  long 
have  been  searching  the  corners  of  the  earth  for  oil,  without  recognizing 


DISCUSSION  7 

the  possibilities  at  home.  I  would  like  to  ask  Mr.  Veatch  whether  any 
chemists  have  ascertained  what  constituents  in  the  oil  are  responsible 
for  its  susceptibility  to  oxidation.  He  says  that,  "  while  it  is  of  paraffin 
base,  it  oxidizes  even  more  rapidly  than  an  asphaltic  oil."  Can  he  give 
us  the  percentage  of  unsaturated  hydrocarbons,  or  any  similar  informa- 
tion concerning  the  chemical  nature  of  the  oil?  This  experience  in 
England  indicates  the  possibility  of  oil  in  other  parts  of  the  world  that 
have  been  neglected  in  explorations. 


OIL   FIELDS    OF    PERSIA 


Oil  Fields  of  Persia 

BY  CAMPBELL  M.  HUNTER,  LONDON,  ENG. 

(New  York  Meeting,  February,  1920) 

PETROLEUM  is  found  in  almost  every  province  in  Persia.  On  the  north- 
ern frontier,  along  the  southern  shore  of  the  Caspian  Sea,  it  is  found  near 
Enzelli  and  Shakhtesar  and  gas  at  Khoremabad.  Oil  is  also  found  at 
Gumish  Tepe,  northwest  of  Astrabad,  on  the  southeastern  shore  of  the 
Caspian  Sea.  Further  inland,  to  the  south  of  Astrabad,  oil  is  found  at 
Dchahkuh-i-balae,  also  on  the  margin  of  the  Khorasan  desert  at  Semnan, 
115  mi.  (35  m.)  east  of  Teheran. 

Along  the  western  frontier,  from  northwest  to  southeast,  oil  is  en- 
countered at  Ouschachi,  north  of  Lake  Urumieh;  in  the  province  of 
Azerbaijan,  at  Zohab,  Khanikin,  and  other  places  in  the  district  of 
Kormanshah  in  the  province  of  Ardelan.  Further  south,  in  the  province 
of  Luristan,  oil  is  found  east  of  Mendeli  and  in  the  Pusht-i-kuh  districts. 
Considerable  quantities  of  oil  are  also  obtained  from  Schuster,  Maidan- 
i-Naphtun,  Ram-Hormuz,  Beheban,  which  are  almost  on  a  straight  line, 
running  northwest  and  southeast  along  the  foothills  of  the  Bakhtiari 
Mountains.  At  Ahwaz,  in  the  province  of  Arabistan,  oil  has  been  found 
along  another  range  of  hills  whose  axis  also  lies  in  a  northwest-southeast 
direction. 

In  the  Fars  province,  boring  for  oil  has  taken  place  at  Daliki,  and 
indications  of  oil  are  found  at  Kheri,  Fasa,  Darab,  and  other  places. 
A  gas  show  is  also  recorded  at  Kuhi-Sung-Atush  in  this  province,  30  mi. 
(48  km.)  east  of  Darab.  In  the  south  of  Persia,  oil  is  encountered  on 
Qishm  Island,  also  at  Ahmedi  and  other  places  north  of  Bunder  Abbas. 
On  the  southeastern  frontier,  oil  is  found  on  the  Sarhad  range  of  hills. 
Thus,  oil  indications  have  been  noted  over  a  distance  of  approximately 
1100  mi.  along  the  western  and  700  mi.  along  the  northern  frontiers  of 
Persia. 

HISTORY 

The  first  working  of  oil  in  Persia  of  which  there  is  any  record  took 
place  at  Kir-ab-us,  Susiana,  now  known  as  Kirab,  about  57  mi.  northwest 
of  Schuster.  Herodotus  (about  B.  C.  450)  reported  a  well  near  Ardericca 
that  produced  three  different  substances;  namely,  asphalt,  salt,  and  oil. 
The  oil,  which  was  black  and  had  a  strong  smell,  was  called  Rhadamance 
by  the  Persians. 


CAMPBELL    M.    HUNTER  9 

At  Daliki,  many  years  ago,  a  well  sunk  to  a  depth  of  124  ft.  pierced 
hard  sandstone  and  blue  clay  and  encountered  semi-solid  bitumen  and 
liquid  petroleum  in  small  quantities.  The  same  company,  the  Persian 
Bank  Mining  Rights  Corpn.,  also  drilled  on  the  island  of  Qishm,  though 
unsuccessfully.  Later,  surveys  at  Zohab  and  near  Schuster  indicated  more 
favorable  conditions.  In  the  former  district,  oil  has  been  exploited  for 
centuries  from  primitive,  shallow,  hand-dug  wells,  some  being  reported 
to  have  yielded  oil  in  undiminished  quantities  for  upwards  of  50 
years. 

In  1903,  W.  K.  D'Arcy,  prompted  by  rumors  of  oil  in  Persia,  started 
a  systematic  investigation  of  the  country,  and  in  1903-4  drilled  two  wells 
at  Kasr-i-Shirin,  one  to  a  depth  of  800  ft.  (243  m.)  and  the  other  to 
2100  ft.  (640  m.) .  Drilling  was  conducted  in  various  districts,  but  without 
any  great  success.  After  about  £200,000  ($1,000,000)  had  been  spent  in 
this  way  and  there  were  serious  thoughts  of  abandoning  the  whole  proj- 
ect, D'Arcy  heard  of  oil  seepages  and  springs  in  the  neighborhood  of 
Schuster  and  had  these  examined.  After  overcoming  much  opposition 
from  the  natives,  a  concession  was  secured  and  drilling  begun.  The  first 
bore  hole,  at  a  depth  of  1100  ft.,  pierced  the  oil  sands  and  the  oil  spouted 
to  a  height  of  70  ft.,  carrying  away  the  derrick. 

In  1909,  the  Anglo-Persian  Oil  Co.  was  formed  with  the  object  of 
working  the  concession  obtained  by  Mr.  D'Arcy  from  the  Persian  Govern- 
ment in  1901.  This  concession  runs  for  60  years,  from  May,  1901,  and 
gives  the  exclusive  right  to  drill  for,  produce,  buy,  and  carry  away  oil 
and  petroleum  products  throughout  the  Persian  Empire,  except  in 
the  provinces  of  Azer,  Badjan,  Gilan,  Mazanderan,  Astarbad  and 
Khorasan. 

Before  the  formation  of  this  company,  preliminary  examinations  and 
tests  had  been  carried  out  in  compliance  with  the  terms  of  the  concession, 
by  the  First  Exploitation  Co.  The  concession  to  the  company  provided 
for  the  allotment  to  the  Persian  Government  of  £20,000  fully  paid  shares, 
as  well  as  a  cash  payment  of  £20,000,  and  a  royalty  of  16  per  cent,  of  the 
net  yearly  profits. 

On  the  inception  of  the  Anglo-Persian  Oil  Co.,  the  actual  holding 
of  the  First  Exploitation  Co.  was  limited  to  1  sq.  mi.  in  the  Maidan-i- 
Naphtun  field,  which  is  situated  in  a  territory  belonging  to  the  Bakhtiari 
Khans.  The  agreement  with  the  latter  tribes  provides  that  they  shall 
receive  3  per  cent,  of  the  shares  in  any  company  formed  to  work  oil  in 
their  country;  and  to  facilitate  the  working  of  the  agreement,  it  was  de- 
cided to  form  a  second  subsidiary  company,  known  as  the  Bakhtiari  Oil 
Co.,  Ltd., to  work  the  remainder  of  the  oil-bearing  lands  in  the  Bakhtiari 
country.  All  the  shares  of  these  two  companies  not  held  in  Persia  are 
the  property  of  the  Anglo-Persian  Company. 

The  concession  taken  over  by  the  Anglo-Persian  Oil  Co.  covers  an  are 


10 


OIL   FIELDS   OF   PERSIA 


of  some  500,000  sq.  mi.,  only  a  small  part  of  which  has  been  examined. 
In  1914,  the  British  Government  decided  to  take  an  interest  in  the  devel- 
opment of  the  Persian  oil  fields,  and  to  this  end,  entered  into  an  agreement 
with  the  Anglo-Persian  Oil  Co.  under  which  they  took  up  1000  £1  pre- 
ferred and  2,000,000  £1  ordinary  shares. 


—  PERSIA  — 

REFERENCE 

•  Oil  Wells  Proved  Areas  • 

•  Reported  Oil  Shows 

mmnmt  Anglo  Persian  Oil  Company*s  Concession 


In  1917,  the  Russo-Persian  Petroleum  Co.  obtained  from  the  Persian 
Government  an  exclusive  concession  for  prospecting  for  oil  in  the  district 
of  Ardebil,  and  in  the  provinces  of  Gilan,  Mazanderan,  and  Astrabad. 
In  the  same  year,  the  same  company  purchased  a  number  of  oil-carrying 
steamers  and  sent  out  a  party  of  geologists  under  Prince  Ameradzhebe. 


CAMPBELL  M.  HUNTER  11 

GEOLOGY 

For  the  purpose  of  this  paper,  Persia  may  be  divided  into  three 
areas:  Northern  Persia,  embracing  the  provinces  of  Azerbaijan,  Gil  an 
and  Mazanderan;  western  Persia,  in  which  lie  the  provinces  of  Ardelan, 
Luristan,  Bakhtiari,  Arabistan,  Pars,  Laristan  and  the  Island  of  Qishm; 
southeastern  Persia,  comprising  the  district  of  Mekran. 

The  oil-bearing  region  in  northern  Persia  lies  between  Lake  Urumieh 
and  the  Caspian  Sea,  a  distance  of  about  200  mi.  in  breadth,  and  belonging 
chiefly  to  the  Tertiary  period.  In  the  north  of  this  region  at  Ahar,  natural 
shows  of  petroleum  are  seen  in  a  stratum  of  apparently  foraminiferous 
sandstone,  which  gives  off  petroleum  emanations  a  few  feet  below  the 
surface.  There  are  also  several  mud  volcanoes  in  this  district.  Be- 
tween Ahmenabad  and  Ahar,  the  region  is  terraced  in  asymmetrical  folds, 
the  principal  axis  of  folding  lying  roughly  due  east  and  west  with  syn- 
clines  about  2  mi.  apart,  the  dip  on  the  one  side  being  between  65°  and 
75°  and  on  the  other  between  12°  and  15°. 

To  the  south  of  Ahar,  the  greater  part  of  the  formations  belong  to 
the  upper  Carboniferous  period;  and  in  the  Savalian  Kuh  Mountains 
in  the  southeast,  rock  salt  and  gypsum  are  found  in  large  quantities. 
Faulting  is  very  prevalent  in  this  range,  associated  with  numerous  highly 
petroliferous  mud  volcanoes. 

East  of  Ahar,  at  Ardebil  on  the  Mugan  steppe,  extensive  shell  beds 
resting  on  rocks  of  Pliocene  age  similar  to  those  found  at  Baku  exist;  it 
is  thought  that  the  oil  fields  of  northern  Persia  are  a  continuation  of  those 
of  Baku.  Similar  shell  beds  exist  near  Marand  almost  due  west  of 
Ahar,  and  near  Sofian  and  Tabris,  which  is  built  on  alluvial  beds  of  Miocene 
age.  The  country  east  of  Tabris  belongs  to  the  Mesozoic  period  and 
contains  very  considerable  deposits  of  rock  salt  and  gypsum.  In  a  de- 
pression close  to  Sirab,  traces  of  oolite  are  found;  and  north  and  south  of 
this  site  Carboniferous  shales  are  met  with. 

The  regional  tectonics  of  the  Belfathemar  divide,  which  lies  to  the 
south  of  Sirab,  consist  of  a  lengthy  anticlinal  fold  along  which,  at  several 
places,  oil  and  gas  escape;  in  warm  weather  fumes  of  sulfuretted  hydrogen 
and  sulfur  dioxide  are  found  in  the  gulleys.  It  is  the  belief  of  Charles 
Bouvard,  Sir  Boverton  Redwood,  and  many  others  that  the  petroleum 
of  northern  Persia  is  of  organic  origin.  Toward  the  end  of  1917,  a  geolog- 
ical survey  of  Gilan  and  Mazanderan  was  in  contemplation  on  behalf 
of  the  Russo-Petroleum  Co.,  which  has  acquired  concessions  in  these 
provinces. 

The  geology  of  southern  and  western  Persia,  especially  to  the  north 
of  the  Persian  Gulf,  has  been  investigated  on  a  comprehensive  scale  by 
Doctor  Pilgrim  who  gives  the  following  geological  formations  in  descend- 
ing order: 


*od  d«td  «oraJ  rarf  of  littoral;  rad 
«  of  tot*  oT  ThMfei  OBMW,  alfeffom  oT  M«*v 


uaH 


i  and  iotorlMd4«d«tr*t«  of  rock  gypsum, 

,,,,,,,,„„,  n«mtoM*. 

tow  oT  Pffrf*,'  MUM**,  and  Bahrain 


In  connect)  u,<  ,,,]  ^<0|ogy  oT  WMtern  And  wwthern  Perain 

roo#t  iroporttt/    »,i  n.«  -  :-.MJ.      -  >}.•  i>akktli*if  «dHo/ 

FiMf  Mfoi,  l>y  far  the  mo«t  import*»t  /UMJ  widespread 

of  th<^  three,  In  mbdMM  blO  tftfiM   dffUooi^  vj/..:Bfl«ttlorgypium 

bed*,  plateau  !,•  d  J  bed*.    According  to  Don.or  J'jlf/.u 

J   U.'    !;.».-.  ,-<  n«  ;-,  MMM  of  l;iyri«  <,\  io«:l-   ;iho«jl.  JO  f  I, 


clayi,  and  «hale»,    The  thicknem  of  tbene  ba»aJ  bed*  w  »t«ti"l  io  »/• 
1000  ft,  and  they  appear  to  to  repraented  f  rom  take  Urumleh,  in  the 
north,  to  J5under  Abba*,  in  the  *outh,    They  are  of  reddwh  color,  due  to 

non  oxi.lir     c:oiifoiiu;thl.y  ov  ilyini/  i.he  ba*al  bed*,  but.  pritlj  no 

|ji.«    «il    tli-in.-inri-tUoii,   an-   I.I,.-   pi;,!.          ,,.  -:  :...,.   <  xl.c/Mj   hoin 

pl;.n,  to  liunditr  Ahlmw.     'J'li^w:,  Dodo/  iMj.'/uncon*ider*  to  bit  il,«- 
e*t  of  the  Far*  *erie*  with  a  thickne**  of  from  14,000  to  16,000  ft  n 
to  4576  HI.)  at  Kotal  Mai',,  but  rapidly  DH/./.H^  to  8000  n   i,.-i  •/,-..„ 

K.Mj.uhil-.h.-i  pl;un  ;ifi«l  MM-  Kol.al  K;un;irjj.      'JJji-y  roii,-.i,-.l.  of  hliji:  ;tf,'l  M  -1 

clay*,  or  marl*,  alternating  with  *and*tone*  m-i  i.i.mly  bedded  fo**il- 
iferoua  HiJiiitOilMi>    The«e  limeftonei  are  most  frequently  fou/.  i  b  i  !.• 
lower  todi  and  the  *and*tone*  predominate  in  the  upper. 

i  IM  pi;,i.  ;..u  I,.,]    ,,  (n  i  „  merge  into.tlia  coa*tal  bed*,  which  v;,;V  Croa 

itOO       h,        1000      II         II.      11,1'    I'll.     ••     ;.l,.j        ,,-        .    -,-npr,     ,    ,j      ,,|      ,,;,!,       ;,,;,,       ,    |;,  ,,, 

marl*,  pa**ing  fom^time*  into  *oft  argillaceous  lime*tone.  Interbedded 
with  thwe  are  thin  oalcareou*  band*  crowded  with  shell*  and  grit  Raft- 
ing with  great  unconformity  ofl  <i"  l(1ar«  *erie*  i*  the  Bakhtiari  *erie*, 
which  consists  of  dotrital  deposit  -  <  >  i  ,,  ,i  ,  ,,.-,,  .  ,,,  ,  ,!,.,,,! 
i  ooo  ft,  thick,  and  IJHH  UM  its  most  characteristic  rock  a  conglomerate  of 
red  and  green  chert  pebbles.  This  *m«r«  in  pntdjoally  unforwilifi  rou 

ami  ir:  i,.,l.  inoir  i.  ,:«•!,  I    Ili.-ui   UK     I'll.  i.  .  >,.    ;.JM 

111    it   pap«T   M-ail    |,I.|'«,M.    Ih.-   I;i;-lil,ul«    ol    l'«-l.n,l«-iiin   'I  <  «  lu,«,l«,}'i    I      n, 

London  (in  1018),  Messrs,  Busk  and  Mayo,  describing  tin  )'.  .i.htiari 
country  arid  dealing  with  these  sen  !<  M!<  \.\\t-  I<'arH  scries  into  a  lower 
gypsiferous  group,  varying  in  thicknenh  hum  Jooo  i.,  :;:,f)0  n,  nun  \(l  /<,;> 
m,);  a  middle,  or  passage,  ^roup,  himilar  to  Docioi  rilfn.,,';,  plah-;m 


CAMI'ltl-  I.I.    \t.     m    '.  (  i  r< 


group,  imt  with  *  thickness  rarely  exceeding  1000  ft.;  and  an  upper,  or 
argttlaoeous,  group  consisting  of  purple  Mid  lid  thai**  and  clay*  with 
intercalated  massive  sandstones,  consisting  of  chert  grains  Mounted  by 
a  calcareous  matrix*  Du»  to  the  presence  of  plant  remain*  and  the  ab- 

*»ricc»of  marine*  fo^il*,  th«»y  <-oriMd<-r<  d  1  1,,.  i,PP,  r  Kmup  ic,  l,<  -i,f  !•»<  uMm,< 
origin  and  about  2700  f<  .  Ihmk. 

The?  Hakhfiari  wri**,  which  ihry  cjoiiMdrr  a  M-dime-nt  df  DOB  BMttfa 
origin,  being  deposited  during  a  period  of  earth  movement  producing  up  - 

lift  :iti<i  d<t>r<*fa  riloriK  W<>11  dofm<  d  Imrs,  »&&!  ,!*  K,rc,t1<M  (huKtu:,- 
c,f  :tl.<,uf  l."»;()(KI  ft.  (<K)7;>  rn.)  in  (he  undine,  thu:-  {<..tn«!  The  |ow<»i 

group  of  thin  ttrie*,  about  12,000  ft.  thick,  consist*  of  cUyii,  thaiei,  and 

.t,f«..:tl:tt..l     ::,.,.  1-1,   r,cW    ritul    fcir^loitlc  Trif  c  -s    ;tl     <M    |»l:irc^,    p:t  t  f  inila  .  1  x 

toward  the*  top  of  the  group,  which  an*  often  1500  ft.  thick  and  are  of 

cMlaic;  form.     Although  oil  :«nd  oily  r<  >Kiu<  ^  rttv  fouml  n,  p.-uf>  d  |U| 

group  <  >  •  ;.r«  fliougMtobt  iimply  duttertdaporition  from  the  adjacent 
Fan  iMriet.  The  upper  group  of  thin  «erie<i  rente  uneonformably  upon  all 
rock*  b«»low,  exeept  in  the  nynclinal  troughn,  and  conniuU  of  conglomerate 

of  wc-ll  rfiutulfd  Inru^loric  :tnd  «lut(    p<hl.lcr<  u.ll  rutirrifrd  ((.F«fl,<»J    :,.>.) 

about  2000  ft.  thick.  Tht  typical  «y  nclint  in  the  Bakhtiari  district  mc»  A- 
suren  about  7  mi.  (11  km.)  aero*  and  in  At  trough  ha*  15,000  ft,  of  the* 
Hakhiirm  MTJC-N  ovc-rlyit^  .VKK)  ff  of  l-ar«  NfiM,  Th«'V  OOfirfdCI  *A1 
further  «-:trlh  movc'ir»c>iif>,  ror.liniMnjr,  fo  tlu  i.to<nf.  hnvc  produ«<l  .. 
v<?ry  romplic-ulrd  MTJC:^  of  f.-inhKe  i  struct  ur<>  \\ifh  ihtur-i  f:tul(:>  <  <>mmF  up 
to  the  surface. 

Oil  ho*  been  fc,....d  ...  thi«  district  to  be  contained  in  the  detriul 
limMtonei  forming  the  bane  of  the  Fan  lerie*  and  has  \wn  flowing  at 
Maidan-i-Naphtun,  under  ttrong  pr«*s»jre,  for  the  last  10  yean.  Th» 
accompanying  table  nhows  the  differwicc  between  tht  tbieknewi  of  the 
variou*  formatioiui,  a«  calculated  by  Doctor  Pilgrim  and  Messrs. 
Bunk  and  Mayo: 

t-..»»  ,.•,,.  M,,.,. 


n«ri«i    1,000  19,000 

IkMMU,  1,000  Low«r   or 

MOO 

iteftMtt  Ml,  1«,000    MiddU  or  pom**  awup,  1,000 
CoMUlM»,  1,000     UPSMNT    or    argill«<Mous    group 
2,700 

In  dcicribing  the  Ahwas  Pusht-i-kuh  country,  Messr*.  Husk  and 
Mayo  state  that  there  i*  an  anticlinal  utructure  running  for  100  ml. 
(100  km.)  in  a  went-northwest  and  east-southeast  direction  through 
Ahwas.  This  structure  forms  the  furthest  outlying  fold  of  the  Iranian 
Mountain  chain  Mid  is  asymmetrical,  having  a  steep  vertical,  or  in  v<  t  f  «  i 
dip  on  the  southwestern  face  Mid  a  gentle  slope  on  the  northeastern 

limb.     In  the;  rioighborhood  of  AhwaS,  tllS  SfSSt  rf  ths 


14 


OIL   FIELDS   OF   PERSIA 


form  of  elongated  domes,  and  denudation  has  shown  that  the  lowest  200 
to  300  ft.  (60  to  91  m.)  of  exposed  beds  belong  to  the  middle  group  of  the 
Fars  series. 

There  is  one  main  oil  horizon  in  the  central  field,  which  has  been  proved 
at  depths  varying  from  1200  to  1300  ft.  (365  to  396  m).  This  horizon 
is  responsible  for  the  greater  part  of  the  production  of  this  field;  and  as 
the  oil  is  found  in  a  hard  porous  limestone,  a  steady  production  is  obtained 
with  little  necessity  for  cleaning  out  the  wells. 

At  the  White  Oil  Springs,  two  seepages  occur  on  the  crest  of  the  fold, 
from  which  a  colorless  oil  resembling  kerosene  is  obtained.  The  produc- 
tion amounts  to  about  20  gal.  (75  1.)  per  day,  and  is  used  by  the  natives 
for  domestic  purposes. 

The  Ahwaz  anticline  is  about  36  mi.  (58  km.)  to  the  southwest  of  the 
Maidan-i-Naphtun  fold;  and  although  no  evidence  of  petroleum  appears 
at  the  surface,  the  White  Oil  Springs  horizon  is  expected  to  exist  at  no 
great  depth. 

At  Qishm,  oil  issues  from  the  lowest  exposed  beds  at  two  places, 
about  J£  mi.  apart.  The  seepages  are  not  considerable. 

TECHNOLOGY 

There  is  little  published  information  relating  to  drilling  methods  on 
the  Persian  oil  fields.  D '  Arcy,  in  his  early  exploration  work,  employed 
Canadian  drillers  and  Canadian  drilling  rigs.  This  system,  but  with  the 
wire  rope  taking  the  place  of  the  old-fashioned  drilling  rods,  is  now  exten- 
sively used  on  the  field,  though  rotary  drilling  has  been  tried.  Inserted 
joint  casing  is  generally  used,  as  formations  encountered  give  little  trou- 
ble through  caving.  Considerable  gas  is  yielded  by  the  wells  and  is  used 
under  the  boilers. 

TABLE  1 


Fractions 

Flash 

Location 

cifit 
Grav- 
itv 

Point 
of 
Crude, 
De-  r 

Ben- 
sine, 

Kero- 
sene, 

Lub- 
ricat- 
ing 

Sulfur 

Odor 

Color 

II*  jr 

grees   ! 

Per 

Per 

Oils, 

F. 

Cent. 

Cent. 

Per 

Cent. 

Schuster  District. 

0.927 

27.0 

45 

Dark  green 

White  Oil  Springs 

(Ahwas)  

0.773 

Present 

Inoffensive 

Light  straw 

Tchiah       Sourlch 

0.815 

Low 

9.4 

57.6 

0.4  per  cent. 

Inoffensive 

Brown, 

(Near  Kasr-i- 

present 

strongly 

Shirin). 

fluorescent 

DaUki  

1.016 

170 

Present 

Strongly     of 

Dark  brown 

sulfuretted 

hydrogen 

Qjshm  

0.837 

100 

Pleasant 

Brownish  red 

DISCUSSION  15 

No  recent  production  figures  have  been  published,  but  it  is  understood 
that  the  wells  come  in  as  gushers  and  continue  to  flow  for  a  considerable 
time.  One  well,  at  least,  is  reported  to  have  yielded  over  100,000  tons 
of  oil  by  flowing.  Early  in  1919,  it  was  stated  that  the  wells  already 
drilled  were  estimated  to  be  capable  of  producing  5,000,000  tons  per 
annum.  Table  1  gives  brief  particulars  of  some  of  the  oils. 

From  Maidan-i-Naphtun,  which  is  situated  about  800  ft.  above  sea 
level,  the  oil  is  conveyed  to  the  refinery  at  Abadan  through  two  pipe 
lines  of  6-in.  and  10-in.  (15  and  25  cm.)  diameter,  the  distance  being 
about  145  mi.  (233  km.) .  The  diameter  of  the  former  pipe  line  is  increased 
to  8  in.  about  53  mi.  from  the  field  to  enable  the  production  from  White 
Oil  Springs  and  Ahwaz  to  be  pumped  to  the  refinery.  Upon  the  comple- 
tion of  certain  additional  pumping  stations,  the  joint  pipe  lines  will  have 
a  total  carrying  capacity  of  about  3,000,000  tons— say  22,000,000  bbl 
The  refinery  at  Abadan,  which  is  an  island  at  the  head  of  the  Persian 
Gulf,  was  completed  in  1913,  with  an  estimated  annual  throughput 
capacity  of  about  240,000  tons  (1,750,000  bbl.).  Since  then  the  refinery 
has  been  considerably  extended,  and  is  now  capable  of  treating  the  bulk 
of  the  company's  production. 

Initially,  considerable  difficulty  was  experienced  in  eliminating  the 
sulfur  present  in  the  Maidan-i-Naphtun  oil.  Various  processes  were 
tried,  and  it  is  only  within  the  last  year  or  two  that  a  satisfactory  treat- 
ment has  been  evolved. 

PRODUCTION  STATISTICS  AND  FUTURE  POSSIBILITIES 

Up  to  1916,  about  thirty  wells  had  been  drilled  at  Maidan-i-Naphtun, 
all  of  which  were  gushers;  no  wells  had  at  that  time  been  put  to  pump. 
The  production  for  the  year  ending  March,  1912,  was  about  600,000  bbl. ; 
during  the  ensuing  six  months  the  yield  had  been  increased  to  1,000,000 
bbl.  Since  then  a  considerable  number  of  additional  wells  have  been 
brought  in  while  a  still  larger  number  have  been  drilled  to  the  oil  sand, 
but  not  completed  pending  the  development  of  increased  marketing 
facilities. 

While  little  information  has  been  published  by  the  Anglo-Persian  Oil 
Co.  on  the  development  of  its  concession,  there  can  be  no  question  that 
Persia  is  destined  to  furnish  enormous  quantities  of  oil,  and  to  take 
a  leading  position  among  the  world's  great  oil-producing  countries. 
From  the  outset,  the  company's  production  has  been  greatly  in  excess  of 
its  transporting,  treating,  and  marketing  facilities. 

DISCUSSION 

THE  CHAIRMAN  (E.  DEGOLYER,  New  York,  N.  Y.).— The  Persian 
fields  are  being  operated  by  the  Anglo-Persian  Oil  Co.,  of  which  the  British 
Government  has  control,  under  what  amounts  to  a  monopoly.  According 


16  OIL    FIELDS   OF   PERSIA 

to  the  company  reports,  some  of  the  wells  discovered  are  among  the 
largest  in  the  world.  The  country  is  becoming  extremely  important  in 
the  production  of  petroleum  at  the  present  time.  According  to  the 
estimate  of  the  United  States  Geological  Survey  in  1918,  Persia  produced 
7,200,000  bbl.  of  oil,  and  was  fifth  in  importance  among  the  producing 
nations. 

The  Chairman  of  the  Board  of  the  Anglo-Persian  Oil  Co.,  in  reporting 
to  the  stockholders  in  1918,  mentioned  a  well  that  had  produced  1,500,000 
tons  with  no  apparent  diminution  in  pressure  and  no  apparent  diminu- 
tion in  productive  capacity.  I  think  that  American  petroleum  geologists 
and  technologists  have  been  overlooking  the  importance  of  the  Persian 
fields  as  a  source  of  supply. 

DAVID  WHITE,  *  Washington,  D.  C. — In  connection  with  the  description 
of  the  oil  indications  of  Persia  and  Mesopotamia,  mention  should  be 
made  of  the  recent  publication  by  the  Hamburg  Colonization  Insti- 
tute of  a  rather  extensive  memoir  by  Walter  Schweer.  This  report, 
which  was  evidently  compiled  for  German  consumption  when  the  war 
should  be  over,  contains  many  details  concerning  the  distribution  and 
character  of  the  oil  indications,  with  something  of  the  geology  and  the 
concessions  held  by  various  countries  in  Turkey,  Palestine,  Arabia, 
Syria,  Persia,  and  Armenia.  This  report  will  be  found  very  valuable  and 
helpful  by  Americans  interested  in  the  great  potential  oil  fields  of  the 
near  East. 

*  Chief  Geologist,  U.  S.  Geol.  Survey. 


OIL    FIELDS    OF   BUSSIA  17 


Oil  Fields  of  Russia 

BY  A.  BEEBY  THOMPSON  AND  T.  G.  MADGWICK,  LONDON,  ENG. 
(St.  Louis  Meeting,  September,  1920) 

FOR  more  than  2500  years,  natural  gas  issues  in  the  Surakhany 
district  of  the  Apsheron  peninsula  were  the  object  of  pilgrimages  by  fire 
worshippers  and  Hindoos  from  Burma  and  India.  Even  as  late  as 
1890,  Hindoo  priests  conducted  ceremonies  in  a  temple  at  Surakhany, 
which  probably  replaced  a  more  ancient  one;  but  later,  the  visits  of  the 
pilgrims  were  prohibited  in  order  to  check  the  spread  of  Asiatic  diseases 
in  that  region. 

For  centuries,  limited  supplies  of  oil  have  been  abstracted  from  shallow 
excavations  in  the  Caspian  oil  belt  and  dispatched  into  the  interior  of 
Asia  and  elsewhere  for  medicinal  and  industrial  purposes.  Statistics 
show  a  yield  of  37,400  bbl.  in  1863,  but  only  since  1869  has  there  been 
serious  development;  in  that  year  the  yield  was  203,000  bbl.  At  that 
time,  hand  digging  was  supplanted  by  drilling,  and  the  enormous  wells 
that  resulted  from  tapping  sources  hitherto  beyond  the  reach  of  operators 
completely  demoralized  the  industry  for  a  time,  owing  to  inadequate 
outlets  for  the  products. 

The  early  activities  in  this  area  were  greatly  hindered  by  annoying 
taxation,  monopolies,  imperial  land  grants,  etc.,  but  when  these  were 
revoked  or  adjusted,  in  1877,  the  industry  sprang  into  prominence  and, 
between  1898  and  1901,  the  Baku  fields  produced  practically  one-half 
of  the  world's  supply  of  oil. 

Within  a  few  miles  of  Baku  lie  the  two  richest  oil  fields  in  the  world; 
viz.,  the  Balakhany-Saboontchy-Romany  and  the  Bibi-Eibat,  the  latter 
constituting  almost  a  suburb  of  the  city.  For  many  years  the  gasoline 
obtained  in  the  refineries  of  the  Baku  area  was  burned  in  pits,  being 
considered  an  undesirable  product,  and  until  1870  the  residue  also  was 
destroyed,  its  value  as  a  fuel  not  being  recognized.  Kerosene  was  the 
main  product  sought  by  the  refiners.  It  was  shipped  across  the  Caspian 
Sea  and  up  the  Volga  to  the  industrial  centers  of  Russia.  Only  on  the 
completion  of  the  Baku-Batoum  railway  did  the  Baku  oil  fields  secure 
important  commercial  communication  with  the  outside  world  through 
the  medium  of  the  Black  Sea.  The  first  tank  steamer  was  successfully 
launched  on  the  Caspian  in  1879,  by  Messrs.  Nobels,  for  transporting 
oil  in  bulk  instead  of  in  barrels.  In  1905,  an  8-in.  pipe  line  to  Batoum 
was  completed;  this  was  capable  of  transporting  to  seaboard  8,000,000 
bbl.  of  kerosene  per  annum. 

VOL.  LXV. 2  . 


18  OIL   FIELDS    OF   RUSSIA 

In  1903,  the  important  Grozny  oil  field  was  proved  by  a  great  flowing 
well  sunk  by  an  enterprising  Englishman,  who,  however,  was  ruined  by 
the  claims  for  compensation  made  by  peasants  whose  habitations  and 
lands  were  destroyed  by  the  deluge  of  oil,  which  could  not  be  controlled 
for  years.  The  property  on  which  the  well  was  drilled  has  since  given 
over  300,000  bbl.  of  oil  per  acre. 

In  1901,  general  interest  was  directed  to  the  Binagadi  oil  field  by  the 
bringing  in  of  a  10,000-bbl.  well.  The  field  lies  close  to  Baladjari  railway 
station  and  only  a  few  miles  from  Baku  and  the  refineries,  to  which  a 
pipe  line  was  subsequently  laid.  In  this  year,  also,  an  important  oil 
field  was  located  at  Berekei;  but  after  a  few  years'  work  hot  sulfurous 
waters  flooded  the  oil  sands  and,  as  no  suitable  means  for  its  exclusion 
were  devised,  the  field  was  practically  abandoned,  although  some  wells 
continued  to  yield  for  years.  Berekei  lies  on  the  Caucasian  railway  near 
the  port  of  Derbent.  The  oil  from  the  field  was  piped  to  the  railway  and 
taken  in  tank  wagons  to  its  destination. 

Another  interesting  field  is  Holy  Island,  off  the  north  coast  of  the 
Apsheron  peninsula,  where  400-bbl.  wells  have  been  struck  and  a  consider- 
able area  has  been  proved  to  be  oil-bearing.  Oil  is  shipped  direct  to  the 
Volga  by  tankers  proceeding  from  Baku.  In  1908,  the  Surakhany  district 
a  few  miles  southeast  of  the  main  Saboontchy  oil  field  was  developed  by 
deep  wells,  and  large  gushers  of  the  typical  Baku  oil  resulted  from 
drilling  beneath  the  upper  light  oil  and  gas-yielding  beds  that  until 
then  had  been  exclusively  worked. 

For  many  years  the  island  of  Cheleken,  off  the  Asiatic  coast  of  the 
Caspian  Sea,  near  Krasnovodsk,  had  been  the  scene  of  some  moderate 
operations;  but  from  1911  onwards  large  yields  were  obtained  from  wells 
sunk  in  the  Ali  Tepe  district  in  the  southwestern  part.  These  wax- 
containing  oils  were  generally  shipped  to  Baku  for  treatment  at  Black- 
town,  the  refinery  suburb  of  Baku. 

In  1909,  the  Maikop  oil  field  attracted  considerable  attention  as  the 
result  of  a  large  gusher  of  light  oil  being  struck  by  almost  the  first  trial 
well  in  the  Shirvansky  district.  Since  that  time,  a  fair  production  has 
been  obtained  although  the  very  prolific  area  was  proved  to  be  small. 
This  field  lies  on  the  northern  flanks  of  the  western,  and  sinking,  end  of 
the  Caucasian  range,  over  which  a  pipe  line  was  laid  to  the  port  of  Tou- 
apse.  Pipe  lines  were  also  laid  to  Ekaterinodar,  where  a  refinery  was 
erected,  as  well  as  Shirvansky. 

A  promising  oil  field  was  developed,  about  1910,  in  the  Emba  district 
north  of  the  Caspian  sea  and  inland  from  the  port  of  Gurieff.  Around 
Dossor,  large  flowing  wells  were  struck  and,  prior  to  the  war,  extensive 
arrangements  were  being  made  to  dispose  of  the  product.  Pipe  lines 
were  laid  to  Bolshaya  Rakashka,  where  refinery  operations  were  con- 


A.  BEEBY  THOMPSON  AND  T.  G.  MADGWICK  19 

ducted,  and  submarine  pipe  lines  were  carried  through  the  shallow-water 
belt  to  facilitate  shipment  of  the  products  up  the  Volga. 

A  single  Turkestan  field,  in  Fergana  on  the  Trans-Caspian  Railway 
at  Chimion,  has  yielded  substantial  supplies  of  oil  that  finds  a  ready 
local  market.  It  is  said  that  at  Maili  Sai  good  productions  resulted  from 
trial  wells  sunk  by  the  government. 

LEASING  OF  OIL  LANDS 

Many  original  grants  of  oil  lands  were  gifts  bestowed  on  court 
favorites,  but  when  some  system  was  introduced  terms  were  based  solely 
on  the  unique  Baku  conditions,  and  prospecting  licenses  of  about  100 
acres  were  granted  from  which  27  acres  could  be  selected  when  oil  had 
been  found.  The  original  annual  rentals  of  $2  per  acre  for  the  first 
ten  years,  increasing  ten  times  each  ten  years,  were  soon  superseded  by 
percentage  royalties,  which  varied  from  25  per  cent,  upwards,  with 
minimum  annual  payments.  At  one  time  tenders  on  a  royalty  basis 
were  publicly  solicited,  but  speculation  led  to  such  absurd  offers  that 
the  government  abandoned  the  practice.  For  instance,  at  times,  oper- 
ators tendered  royalties  of  75  per  cent,  with  large  minimum  payments 
merely  to  protect  their  boundaries  from  aggressive  competitors. 

The  Cossack  lands  of  the  Terek-Kuban  provinces  were  subject  to 
a  rental  of  $5  per  acre  per  annum  and  about  4  c.  per  bbl.  royalty  for 
the  first  120,000  bbl.  and  2  c.  per  bbl.  afterwards;  but  rights  were  reserved 
to  revise  the  royalties  after  12  years.  Insistence  in  perpetuating  the  old 
leasing  laws  based  on  the  unique  oil  fields  of  Baku  has  been  a  great  hin- 
drance to  prospecting  in  Russia,  and  it  is  to  be  hoped  that  some  more 
rational  policy  will  be  introduced  in  the  near  future. 

DISPOSAL  OF  RUSSIAN  OILS 

The  products  of  the  Baku  oil  fields  go  largely  to  supply  the  internal 
demands  of  Russia  through  the  medium  of  the  Caspian  Sea  and  the  river 
Volga,  although  the  freezing  of  the  northern  Caspian  and  the  Volga  in 
the  winter  months  restricts  movements  of  oil  to  about  8  months  in  the 
year.  A  pipe  line  and  railway  to  Batoum  are  available  for  the  convey- 
ance of  lamp  oils  and  other  oil  products  to  the  Black  Sea,  where  ocean 
vessels  can  approach  via  the  Dardanelles.  The  large  refineries  are 
situated  at  Blacktown,  a  suburb  of  Baku. 

Oil  from  the  Grozny  field  and  refineries  is  either  piped  to  the  port 
of  Petrovsk  on  the  Caspian  Sea  or  sent  by  rail  to  Novorossisk  on  the 
Black  Sea.  From  Holy  Island  and  Cheleken,  oils  are  mainly  sent  to 


20  OIL    FIELDS    OF   RUSSIA 

Baku  for  treatment;  while  the  North-Caspian  (Emba)  oils  are  shipped 
at  Bolshaya  Rakashka  for  transmission  up  the  Volga.  Central  Asian 
oils  find  a  ready  Asiatic  market  and  are  useful  for  the  Trans-Caspian 
railway  service.  Maikop  oils  can  either  be  pumped  to  Touapse  on 
the  Black  Sea  or  to  Ekaterinodar,  a  large  town  that  feeds  a  wide, 
fertile,  agricultural  region.  Extensive  tank  farms  are  situated  at  Baku, 
Grozny,  Batoum,  and  Novorossisk;  also  up  the  Volga,  where  the  winter 
supplies  are  accumulated  during  the  summer  months. 

OIL  MANIFESTATIONS 

Probably  no  country  in  the  world  exhibits  a  greater  display  of  oil- 
field surface  phenomena  than  Russia.  There  are  thousands  of  square 
miles  flanking  the  Caucasus  Mountains  and  encircling  the  Caspian  Sea 
that  justify  an  investigation.  Difficulties  of  language,  inaccessibility, 
danger  to  life,  indifference  of  the  authorities  to  their  mineral  resources, 
and  irritating  restrictions  have  contrived  to  suppress  any  initiative  that 
existed.  For  miles  around  the  Baku  oil  fields,  the  oil  series  lie  spread 
out  like  the  leaves  of  a  book  under  the  nearly  desert-like  surroundings  of 
that  devastated  region.  Mud  volcanoes  on  a  gigantic  scale  in  every  stage 
of  activity  may  be  witnessed,  as  well  as  perpetual  fires  fed  by  incessant 
issues  of  natural  gas.  Acres  of  asphaltic  residues  and  streams  of  viscous 
oils  oozing  from  immense  thicknesses  of  oil-soaked  sands  are  common. 
These  phenomena,  mingled  with  sulfurous  waters,  present  problems  for 
study  that  are  nowhere  else  reproduced  on  such  a  vast  scale.  Over 
extensive  areas,  shallow  hand-dug  wells  sunk  into  the  outcropping 
inclined  or  vertical  strata  yield  appreciable,  and  often  considerable, 
quantities  of  oil. 

Many  equally  imposing  exhibits  of  oil  phenomena  may  be  seen 
on  Holy  Island  and  Cheleken,  where  for  miles  numerous  oil  residues, 
gas  exudations,  and  sulfurous-  and  salt-water  issues  may  be  examined 
along  the  outcropping  beds.  Fierce  outbursts  of  oil  and  gas  occasionally 
startle  the  inhabitants,  cause  damage  to  property,  and  loss  of  life.  Twice 
within  the  writer's  knowledge,  such  outbursts  in  the  Yasmal  Valley  have 
caused  conflagrations  that  illuminated  the  sky  for  miles  around  each 
night.  Big  outflows  of  oil  have  also  been  recorded;  and  during  earth- 
quakes, considerable  alarm  has  been  occasioned  by  the  ignition  of  gas 
that  issued  from  cracks  in  the  earth.  Little  less  interesting  are  the  great 
mud  volcanoes  of  the  Taman  peninsula,  which  area  has  not  received 
the  attention  its  manifestations  merit. 

An  interesting  phenomenon  is  the  submarine  gas  issue.  Prior 
to  the  development  of  the  Baku  oil  field,  several  places  in  the  Caspian 
Sea  were  known  where  the  ebullition  caused  by  escaping  gas  was  suf- 
ficient to  capsize  boats. 


A.  BEEBY  THOMPSON  AND  T.  G.  MADGWICK  21 

GEOLOGY 

As  is  the  case  in  many  other  oil  fields,  structure  is  the  dominating 
feature  of  the  chief  oil  fields  of  Russia.  Comparatively  simple  partial 
domes  characterize  the  two  great  fields  of  Baku,  but  both  have  flanks 
on  one  side  where  the  oil-bearing  series  outcrop  and  display  those  surface 
phenomena  usually  associated  with  oil.  The  whole  series  of  Tertiary 
strata  in  which  the  oil  is  secreted  consists  of  unconsolidated  clays,  sandy 
clays,  and  sands  of  all  grades  of  fineness  that  readily  break  down  and 
crumble  when  pierced  by  the  drill.  Their  fragile  nature  is  the  cause  of 
unusual  difficulties  in  drilling,  as  throughout  a  thickness  of  over  3000  ft. 
there  are  constant  irregular  and  ill-defined  alternations  of  sands  and  clays 
that  merge  into  one  another  in  a  way  that  makes  a  log  very  unreliable 
when  prepared  from  collected  samples.  Some  sands  are  charged  with 
oil,  some  with  gas  alone,  and  others  with  oil  and  gas.  Many  of  the  water- 
bearing quicksands  run  freely  on  penetration  and  fill  the  hole  to  a  depth 
of  hundreds  of  feet.  At  times,  too,  oil-saturated  clays  continue  to  ooze 
into  the  well,  rendering  progress  very  difficult. 

Certain  sandy  horizons  can  occasionally  be  traced  for  some  distance 
and  definite  water  and  oil  horizons  have  been  located  within  restricted 
areas.  Generally,  however,  the  pliable  beds  have  been  so  contorted  and 
crushed  that  no  single  bed  can  be  recognized  for  any  considerable  dis- 
tance. Geological  study  was  always  made  more  difficult  by  the  further 
disruption  the  beds  sustained  when  rich  oil  sands  were  struck.  Masses 
of  surrounding  strata  were  expelled  on  penetrating  a  rich  oil  sand; 
in  addition,  thousands  of  tons  of  sand  was  either  ejected  with  oil 
during  flows  or  removed  with  the  oil  during  its  abstraction.  As 
much  as  50  per  cent,  sand  (by  weight)  has  been  suspended  in  the 
oil  for  a  time,  and  often  10,000  tons  of  sand  have  been  ejected  daily, 
for  some  weeks,  from  a  well  piercing  a  virgin  and  prolific  sand  body. 

Stratigraphy 

The  oil-bearing  rocks  of  the  Russian  oil  fields  are  of  Miocene  and,  to  a 
less  extent,  of  Oligocene  age;  that  is  to  say,  occur  in  the  deposits  of  the 
old  Caspian-Mediterranean  sea  that  surrounded  the  Caucasus  and  gener- 
ally lie  unconformably  upon  the  more  highly  disturbed  Cretaceous  beds. 
The  large  area  covered  by  these  deposits,  particularly  along  the  foot  of 
the  northeastern  slopes  of  the  mountains,  has  enabled  very  many  occur- 
rences of  oil  to  be  noticed.  It  is  these  Tertiary  rocks  alone  that  present 
any  interest,  although  considerable  quantities  of  gas  have  occurred  in 
the  Cretaceous,  a  noteworthy  instance  being  during  the  construction 
of  the  tunnel  on  the  Novorossisk  line.  Oil  seepages  are  likewise  known 
in  the  Cretaceous  rocks. 


22 


OIL  FIELDS   OP  RUSSIA 


Detailed  geological  study  of  this  great  area  has  not  been  attempted, 
in  fact,  published  maps  have  been  confined  to  the  districts  in  which 
development  has  taken  place.  Tabular  columns  are  appended  of  the 
Neftianaia-Shirvanka  area  in  the  Kuban,  or  northwest  area;  the  Grozny, 
or  northeast  field;  and  the  Apsheron  Peninsula,  the  most  eastern  portion 
and  seat  of  by  far  the  most  important  development,  the  Baku  fields. 
These  tables  show  that  the  Miocene  rocks  present  similar  character- 
istics throughout  the  northern  flanks  of  the  mountains  but  that  at 
Baku  there  is  a  distinct  facies,  which  is  largely  concealed  by  the  char- 
acteristic Pliocene  and  Post-Pliocene  formations  of  the  Caspian  Sea. 
Nevertheless,  the  Apsheron  Peninsula  as  a  whole  presents  a  very 
complete  exposure  of  the  succession,  notably  in  its  northwest  corner 
and  in  the  Yasmal  valley  and  adjacent  hills  farther  south,  while  the 
Pliocene  ^and  younger  rocks  are  seen  around  the  fields  and  farther 


TABLE  1. — Section  of  Apsheron  Peninsula  (after  Golubiatnikov) . 


STAGE 


FOHMATION 

Coastal  deposits  of  present  Cas- 
pian extending  to  10  m.  above 
present  sea-level. 

Older  Caspian  deposits  forming 
conglomerates  at  a  height  of  12 
and  26  m.  and  reaching  to  a 
height  of  34  m.  above  present 
sea-level. 

Aralo-Caspian  Terraces  at  a 
height  of  96  and  186.5  m. 
(beds  not  disturbed.) 

Bakunian  (disturbed). 

Apsheronian. 


THICKNESS, 

METERS 

5-10 


Pontian  (?) 


Transition  beds. 


LlTHOLOGlCAL   CHABACTEB 

Sands,    clay,    and    shell   frag- 
ments. 

14      Sands,  clays,  boulders  and  shell 
conglomerates. 


3-6      Limestones,  sands  with  boulders 
and  conglomerates. 

46      Limestones,  sandstones,  sands, 
clays  and  conglomerates. 

453  Limestones,  boulder  limestones, 
oolites,  shell  beds,  sandy  lime- 
stones, calcareous  sandstones, 
sands,  marls,  sandy  clays,  and 
clays;  limestones  predominate 
in  the  upper  beds,  sands  in 
the  middle,  and  clays  in  the 
lower;  the  thick  clay  series 
(110  m.)  contain  layers  of 
tufaceous  sands  at  base. 
76  Dark  colored  clays  interbedded 
with  sand  and  marl;  contain 
gas  at  Bibi-Eibat. 

11.3  Dark  clays  with  interbedded  gas 
sands;  sands  gas  bearing  at 
Bibi-Eibat. 


A.  BEEBY  THOMPSON  AND  T.  G.  MADGWICK 


23 


TABLE  1. — Section  of  Apsheron  Peninsula  (after  Golubiatnikov) . 

(Continued) . 

STAGB  FORMATION  THICKNESS,  LITHOLOGICAL  CHARACTER 


Akchagylian. 


Fresh  water  formation. 


49.4 


490 


Unfossiliferous  series: 

First  series,  sand   oil  bearing      434 

at  Bibi-Eibat. 
Second  series,  sand  oil  bearing      185 

in  Yasmal  Valley. 
Break   hi   the   series   until   the 
Spirialis  beds 
Spirialis  beds.  98 


Dark  colored  clay  shales  and 
shaley  clays  interbedded  with 
limestones  and  white  tufaceous 
sands;  the  sands  are  gas  and  oil 
containing  in  Bibi-Eibat. 

Clays,  sandy  clays,  sands  with 
clay  and  sand;  clays  pre- 
dominate. 

Sandy  clay  series;  sands  pre- 
dominate. 

Sands  and  sandstone  with  inter- 
bedded  clays. 


Siliceous,  calcareous  and  sandy 
clay  rocks  with  interbedded 
ferruginous  sandstones;  in 
places  oil  bearing. 

Cedroxylon  beds.  Dark  colored,  laminated  shales 

with  concretions  of  siliceous 
sandy  rocks. 

Amphisyle  beds.  Shales,  dark,  and  chocolate 

colored,  weathering  yellow. 

Lamna  beds.  Green,  sandy  clay  shales  with 

interbedded  siliceous  sandy 
rocks  and  white  marls;  oil 
bearing  in  places. 

TABLE  2. — Section  of  Grozny  Field  (after  Charnotsky) 


STAGE 
Meotic. 


FORMATION 


Akchagylian 


THICKNESS, 
METERS 


LlTHOLOGICAL   CHARACTER 


Middle  Sarmatian     Beds   with   fish 

formation.                 and  remains  of 

Cetacea. 

1 

Spaniodontella 

0 

Transition  from 

beds. 

§ 

Sarmatian  to  /.t 

Mediterranean. 

Chokrakian. 

Mediterranean          Spirialis  beds. 


Up  to  425  Limestones,     conglomerate    of 
limestone  pebbles,   calcareous 
sandstone,   and  clayey  sands, 
calcareous  clays. 
Unconformity. 

43  Calcareous  (and  shaley)  clays 
with  numerous  limestone  beds. 

50  Shales,  sandy  clays,  clay  sand- 
stones, calcareous  clays  and 
sandstones,  pure  sandstones, 
water  sands. 

370  Shales,  sandy  clays,  clay  sand- 
stones, pure  sandstones,  cal- 
careous sandstones,  limestones, 
(often  nodular) ,  dolomite; 
sandstones  oil  bearing. 
?  Black  shales,  limestones,  black 
nodular  limestones,  dolomite. 


24 


OIL   FIELDS    OF   RUSSIA 


TABLE  3. — Section  of  Neftianaia-Shirvanka 


STAGE 
Meotic. 


THICKNESS, 
METERS 


Upper 
Sarmatian. 


Middle 
Sarmatian. 


Lower 
Sarmatian. 


Middle  Miocene 
Mediterranean 


LOCAL  HORIZON 

Congeria  Panticapea 
beds. 

Mactra  Caspia  beds. 


Beds  with  typical  Mid- 
dle Sarmatian  fauna. 
Cryptomactra  beds. 


Beds  with  Lower   Sar-      400-500 

matian  fauna. 
Beds  with  fish  and  plant 

remains. 


Spaniodon  beds. 


Spirialis  beds, 
j  Chokrakian. 


in  E 


Lower  Miocene.     Oil  formation. 


I 


Upper 
Middle 

Lower 
Senonian. 

Aptian 


Foraminifera  beds. 


Beds  with  Pecten 
Bronni. 


Beds  with  Ammonites. 


LlTHOLOGICAL   CHARACTER 

Dolomitic  limestone,  at 
base  dark  marls. 
Unconformity. 

25-30      Thin  clay  beds,  a  few 
+  thin  partings  of  ferru- 

ginous sandstone,  shell 
beds,  gypsum. 

thin         Dark  gray  clays,  at  top 
beds  of  shells. 
Dark    gray    marls,    at 
base  thinly  laminated 
gray  marls. 
Shell  limestones. 

Dark  gray  marls  with 
beds    of    gray    thinly 
laminated  marls. 
10-15       Compact    marly    lime- 
stones    with     porous 
partings. 
200-400     Dark  marls  and  yellow 

gray  marls. 

20-25      Sands    and    limestone, 
shell  beds,  dark  marls. 
225         Dark  shaley  muds  not 
(Neftianaia)    effervescing    in    HC1; 
beds   of   coarse   sands 
and  sandstones  becom- 
ing  gravels   in   places 
480          or  conglomerates;  most 
(r.  P.  shekh)    beds  contain  oil. 

800         White  clays  and  marls, 
beds  of  shaly  bitumi- 
nous marls. 
Green-gray  marls. 

Unconformity. 

White  chalk  marl  with 
few  beds  of  dark  marls 
and  coarse  sandstones. 
Unconformity. 

Dark  sandy  clays  with 
beds  of  coarse  sand- 
stone. 


east.  The  Grozny  field,  forming  as  it  does  a  very  complete  instance  of  a 
subsidiary  fold,  may  well  be  referred  to  as  a  classic  example  of  the  asym- 
metrical anticline;  it  yields  no  exposures  of  the  older  rocks.  Still  farther 
westward,  in  the  Kuban  area,  the  development  has  been  along  the  mar- 


A.   BEEBY   THOMPSON   AND   T.    G.    MADGWICK  25 

gin  of  the  Tertiaries  where  they  are  creeping  around  the  final  Cretaceous 
anticlinorium  of  the  Main  Range  before  it  disappears  beneath  nearly 
level  younger  formation  in  the  Taman  Peninsula  to  reappear  under  simi- 
lar conditions  in  the  Crimea. 

The  same  formations  occur  south  and  southwest  of  Baku  and  are 
recognizable  across  the  Caspian.  It  is  impossible  to  draw  any  geo- 
logical limit  to  the  oil  province  of  Southern  Russia,  it  must  be  studied  in 
the  future  as  part  of  the  Eurasian  Fields. 


Structure 

Regionally,  the  structure  is  that  of  folding  parallel  to  the  main  ridge 
of  the  Caucasus  with  development  of  asymmetric  folds  along  the  north- 
east side,  more  disturbed  conditions  to  the  south,  and  gentle  plunging 
of  the  Tertiaries  and  Pleistocene  at  the  ends,  with  quite  considerable 
local  folding  in  the  thick  series  of  plastic  rocks  composing  the  earlier 
Tertiaries  of  these  districts.  Two  well  marked  directions  of  folding 
northeast  and  northwest,  of  which  the  former  is  the  older,  are  recognizable. 
The  intersection  of  these  two  lines  at  the  Taman  and  Apsheron  Peninsulas 
leads  to  local  development  of  great  pressure,  which,  acting  on  the  plastic 
material,  gives  rise  to  the  phenomenon  of  "salses, "  or  "mud  volcanoes" 
as  they  are  often  called,  in  which  the  softer  underlying  strata  are  squeezed 
out  in  the  form  of  mud,  associated  with  much  salt  water  and  gas,  the 
latter  being  composed  of  hydrocarbons  and  at  times  emitted  on  a  grandi- 
ose scale.  The  exuded  material  forms  considerable  hills,  at  the  top  of 
which  a  crater  shows  activity,  even  in  times  of  relative  quiescence. 
The  rather  complex  structures  resulting  from  the  intersection  of  these 
folds  are  often  hidden  beneath  the  Pleistocene  rocks,  which  partake 
of  no  folding,  and  the  Pliocene  which  have  suffered  slight  deformation. 
This  is  especially  the  case  in  the  Taman  peninsula.  It  is  also  the  case, 
to  a  certain  extent,  in  the  Apsheron  peninsula  though  good  exposures 
exist. 

The  Apsheron  peninsula  is  built  up  of  Pleistocene  and  Tertiary  rocks 
and  both  the  Pliocene  and  the  Miocene  rocks  are  well  developed.  It  is 
the  Upper  Miocene  that  carries  the  pay  so  far  developed.  The  shell 
limestones  of  the  Pliocene,  which  form  the  Baku  building  stone,  are  less 
easily  denuded  than  the  Miocene  rocks  and  so  form  escarpments  around 
the  oil  fields,  usually  bordering  plateaus,  while  the  Miocene  rocks,  where 
exposed,  form  gently  undulating  country. 

The  Akchagylian  (Upper  Miocene)  contain  abundant  fish  remains 
and  thin  beds  of  volcanic  ash.  The  only  known  occurrence  of  pay  in 
them  is  at  Surakhany;  it  is  of  the  filtered  type  and,  therefore,  secondary. 
The  fresh-water  formation  contains  shell  remains  and  algae.  It  covers. 


26  OIL  FIELDS   OF  RUSSIA 

large  areas  in  the  older  fields  but  is  concealed  at  Surakhany.  The  under- 
lying unfossiliferous  series  forms  with  it  the  source  of  the  bulk  of  the 
oil  hitherto  won  in  Russia. 

The  unconformable  Lower  Miocene,  capped  by  the  hard  siliceous 
limestones  with  very  characteristic  casts  of  Spirialis,  which  form  a  useful 
mapping  horizon,  is  petroliferous;  especially  noticeable  are  the  Oligocene 
fish  shales,  but  these  strata  have  yielded  no  pay. 

Four  directions  of  folding  occur,  northwest,  meridional,  latitudinal, 
and  north-northeast.  The  first,  that  of  the  main  Caucasian  ridge, 
prevails  at  Bibi-Eibat,  Holy  Island,  and  over  much  of  the  northeast  part 
of  the  peninsula;  the  second  at  Surakhany.  Many  folds  are  subject  to 
change,  and  complex  structures  ensue,  in  the  formation  of  which  faulting 
stands  in  close  relation.  Faults  are  usually  of  small  throw  and  coincide 
with  the  axial  crests,  but  three  important  lines  must  be  noted  as  they 
dominate  the  Peninsular  structure.  The  first  is  the  circular  uplift 
following  the  ridges  Kabiriadig-Puta,  Atashka-Shaban-Dagh,  and  Kobi- 
Bos-Dagh;  this  lies  west  of  any  important  developed  area.  The  second 
runs  along  Atashka-Shaban-Dagh,  Gyokmabj-Khurdalan,  and  Binagady; 
and  the  third  through  Fatmagi-Dygia,  Kir-Maku,  Balakhany-Saboont- 
chy-Romany,  and  Surakhany-Zykh.  These  two  lines  form,  with  the 
Bibi-Eibat  fold,  a  horseshoe  line  open  to  the  sea;  it  is  along  this  line  that 
the  big  production  has  been  obtained.  The  last  important  tectonic  move- 
ments took  place  at  the  close  of  the  Upper  Pliocene  period,  the  next 
before  was  at  the  commencement  of  the  Upper  Pliocene,  while  between 
the  Middle  and  the  Lower  Oligocene  much  greater  dislocation  took 
place. 

Oil  Occurrence 

The  following  horizons  are  known  to  carry  oil: 

1.  Middle  Pliocene:  lower  Apsheronian  at  Surakhany  and  Romany. 

2.  Lower  Pliocene :  Pontian  at  Bibi-Eibat. 

3.  Akchagylian:  at  Bibi-Eibat,  Surakhany,  Romany. 

4.  Fresh-water  beds:  at  Bibi-Eibat,  Surakhany,  Romany,  Saboont- 
chy. 

5.  Unfossiliferous   beds:    Puta,    Atashka,     Khurdalan,     Binagady, 
Kir-Maku,  Balakhany,  Holy  Island. 

6.  Lower    Miocene:    (Spirialis)    Puta,   Atashka,   Kobi,   Gyokmabj, 
Khurdalan,  Binagady,  Holy  Island. 

7.  Amphisyle  beds:  Sumgait. 

8.  Lamna  beds :  Western  hills  from  Kobi  mud  volcano  onwards. 
The  impregnation  is  sporadic,  thus  the  phenomenally  rich  fresh-water 

beds  beneath  Bibi-Eibat  and  Surakhany  show  no  signs  of  oil  on  their 


A.  BEEBY  THOMPSON  AND  T.  G.  MADGWICK  27 

outcrops  in  the  adjacent  Yasmal  valley  and  Zykh,  respectively.  These 
facts  lend  weight  to  the  hypothesis  that  their  oil  is  in  secondary  accumu- 
lation, which  would  have  been  facilitated  by  the  downward  increase  of 
permeable  strata  and  the  big  unconformity  above  the  Lower  Miocene. 
The  temperatures  of  the  oil  at  Bibi-Eibat  have  been  acquired  in  accord- 
ance with  the  geothermals,  hence  the  invasion  must  be  mainly  a  long 
accomplished  fact. 

Of  the  eight  horizons,  the  third  has  importance  in  Surakhany  for  gas 
and  "white  oil;'7  the  fourth  is  the  most  prolific  and  is  of  value  in  Surak- 
hany, Saboontchy,  Romany,  and  Bibi-Eibat;  the  fifth  in  Balakhany, 
Binagady,  Holy  Island,  Khurdalan,  on  Atashka,  and  near  Puta  Station. 

Surakhany. — The  Pliocene  and  Miocene  rocks  are  folded  into  a  broad, 
flat  anticline  striking  north  and  south.  Eastern  dips  are  10°  to  20°; 
the  western  4°  to  10°.  The  visible  fold  continues  to  the  north  end  of 
Surakhany  Lake  and  southward  toward  the  faulted  area  at  Zykh.  The 
crest  is  much  faulted  and  in  the  salt  lake  are  numerous  fissures  filled 
with  inspissated  oil,  while  over  a  wide  area  fissures  emit  gas.  The  oil 
zone  having  now  been  proved,  by  drilling,  to  continue  through  to 
Romany,  it  is  probable  that  the  two  areas  are  on  one  curving  fold. 

Gas  springs  occur  over  the  whole  central  part  of  the  district,  in  the 
Lake,  on  the  hill  Atashka  (" eternal  Fires"),  at  the  Temple,  and  in  the 
depression  of  Karatchkhur.  To  sink  20  to  30  ft.  is  enough  to  strike  gas. 
The  upper  gas  beds  cover  an  area  of  4800  m.  by  1500  m.  (1780  acres)  and 
represent  the  apex  of  the  fold.  Outside  this  area,  the  same  beds  contain 
no  gas.  Drilling  has  shown  that  all  porous  beds  in  the  upper  strata 
contain  gas;  the  lower,  gas  and  oil.  From  36  m.  (118  ft.)  to  480  m. 
(1575  ft.),  twenty-three  gas  sands  were  struck,  the  pressure  at  times 
reading  30  atmospheres. 

White  oil  begins  at  200  m.  (656  ft.),  at  the  top  of  the  Akchagylian, 
and  increases  downwards.  Only  the  central  region  is  oil  bearing.  From 
200  to  335  m.  (656  to  1099  ft.)  five  white  oil  sands  were  struck.  The 
specific  gravity  is  0.785. 

Black  oil  was  first  struck  at  480  m.  (1575  ft.)  in  the  fresh-water 
formation,  as  previously  determined  by  Golubiatnikov.  During  recent 
years,  great  development  has  taken  place  below  this.  The  first  horizons 
yielded  oil  having  a  specific  gravity  of  0.820. 

Balakhany,  Saboontchy,  Romany. — A  wide,  faulted  anticline  represents 
the  continuation,  southeast  of  the  mud  volcano  Bog-Boga,  of  two  folds, 
that  of  Kir-Maku  to  the  northwest  and  Binagady  more  westerly.  The 
fold  pitches  to  the  southeast,  disappears  beneath  the  Pliocene  beyond 
Romany,  but  is  probably  continuous  with  Surakhany.  The  fresh-water 
formation  covers  most  of  the  field,  the  unfossiliferous  series  appearing  in 
the  salt  marsh  of  Kir-Maku.  The  oil  in  the  upper  beds  at  Romany  is 
lighter,  in  the  lower  beds  at  Balakhany  heavier. 


28  OIL   FIELDS    OF   RUSSIA 

Bibi-Eibat. — This  is  a  dome  plunging  north-northwest  and  possibly 
beneath  the  sea.  At  its  crest  are  two  subsidiary  parallel  domes,  one 
with  its  apex  on  Group  XIX,  the  other  roughly  on  Group  XX.  Between 
them,  the  shallow  minor  syncline  forms  the  low  hill  running  out  to  sea 
at  Cape  Naftalan.  Much  minor  faulting,  usually  parallel  to  the  major 
axis,  occurs.  The  fresh-water  beds  are  exposed  around  Naftalan  where 
the  best  production  has  been  obtained.  The  beds  are  very  uniform  litho- 
logically,  the  sands  being  fine  to  medium  grained,  the  former  like  dust 
and  known  as  "gas  sands"  to  the  driller,  while  alternating  clay  and  fine 
sand  is  termed  "gas  clay."  "Water  sands"  are  cemented  with  lime, 
"oil  sands"  are  loose  and  when  saturated  with  gas  and  oil  are  thought 
to  resemble  caviar.  The  occurrence  of  hard  concretions  of  sandstone 
probably  accounts  for  the  removed  cementing  material. 

Ignoring  the  beds  of  inspissated  oil  and  gas  and  oil  shows  in  upper 
beds,  the  first  important  pay  was  struck  at  280  ft.  Other  oil  sands  were 
struck  at  intervals  but  were  exhausted  down  to  700  ft.  before  any  study 
of  the  field  was  made.  Between  here  and  640  m.  (2100  ft.)  were  twenty 
workable  sands  with  a  total  thickness  of  120  m.  (390  ft.) .  Water  sands 
were  few  and  it  was  only  below  2600  ft.  that  the  predominance  of  sands 
made  water-shut-off  of  such  importance.  Water  occurs  in  all  sands 
and  made  the  marginal  plots  unprofitable. 

Binagady,  Khurdalan,  and  Puta. — These  areas  are  geologically  much 
alike.  Oil  is  obtained  from  the  unfossiliferous  series,  which  are  folded 
into  much  faulted  anticlines.  The  oil  is  heavy.  Binagady  became 
prominent  as  a  producer  during  the  war;  the  other  fields  are  classed 
in  the  "hand  dug"  production. 

Holy  Island. — The  Pleistocene  beds  here  rest  directly  on  the  unfossil- 
iferous beds,  very  much  disturbed,  with  the  Spirialis  horizon  just  show- 
ing to  indicate  the  succession.  The  fold  is  an  elongated  dome  with  the 
major  axis  northwest;  it  is  asymmetrical  with  overfolded  side  in  places. 
It  is  much  faulted  and  there  is  evidence  of  other  domes  outside  the  de- 
veloped area  (in  the  northern  part  of  the  Island) . 

Seepages  occur  at  the  southern  end  of  the  anticline  and  in  the  central 
salt  marsh  and  mud  volcanoes,  etc.  along  the  crest.  The  oil  has  infil- 
trated into  the  Pleistocene  and  has  formed  Kir  deposits  in  the  sandstones 
of  the  northeast  part  of  the  fold.  This  part  has  been  developed  with 
the  drill,  the  wells  giving  800  poods  daily  from  1300  ft.  The  specific 
gravity  is  0.944. 

Grozny. — Outside  the  Apsheron  Peninsula,  the  most  important  field 
is  Grozny.  Here  are  two  folds.  The  old  field  is  an  elongated  asym- 
metrical dome,  slightly  bulging  outwards  on  its  steep  side,  accompanied 
with  dip  faulting,  which  marks  out  distinct  provinces  as  regards  water 
and  richness  of  pay.  Dips  on  the  north  vary  from  40°  to  90°;  on  the 
south,  from  20°  to  30°  and  flatten  out  at  the  ends  to  6°  to  15°.  The 
length  is  9  mi.  west  northwest. 


A.   BEEBY   THOMPSON  AND   T.    G.    MADGWICK  29 

The  new  Bellik  field  is  a  nearly  symmetrical  fold  and  lies  to  the  east 
of  the  old  field. 

As  shown  by  the  columnar  section,  Table  2,  the  beds  are  of  Miocene 
age,  the  oil  occurring  in  the  Chokrakian  (transition  Mediterranean- 
Sarmatian),  and  they  do  not  outcrop.  Just  at  the  apex  of  the  old  field, 
the  overlying  Spaniodontella  beds  are  exposed.  The  oil  occurs  in 
sandstones  associated  with  shales,  sandy  clays,  limestone,  and  dolo- 
mites; whether  in  situ  appears  doubtful. 

Maikop. — Here  oil  occurs  in  beds  of  Upper  Oligocene  age,  in  a  suc- 
cession of  shales,  marls,  and  sandy  beds.  Beneath  is  a  thick  mass  of 
foraminiferal  marls,  above  are  the  Mediterranean-Sarmatian  beds  of  the 
Chokrakian  limestone.  The  Tertiaries  lie  unconformably  upon  denuded 
Cretaceous  rocks  in  the  oil-field  region  of  Shirvansky,  no  Eocene  beds  being 
interposed,  but  farther  west  these  latter  appear.  The  oil  sand  is  a 
narrow  strip  down  the  dip  and  probably  represents  a  former  river  bed. 
It  is  sealed,  by  overlapping  against  some  of  the  Cretaceous  islands 
penetrating  the  foraminiferal  marls;  the  dip  of  the  Tertiaries  is  10°. 
The  Pioneer  well  was  able  to  show  a  yield  of  375,000  bbl.  from  the  shallow 
depth  of  281  feet. 

About  140  km.  (87  mi.)  westward  lies  Kudako  where  the  first  Russian 
gusher  was  struck,  in  February,  1866,  at  a  depth  of  70  ft.  with  a  reported 
yield  of  1,000,000  poods  (120,500  bbl.).  Subsequent  wells  reached 
700  to  1050  ft.  under  conditions  similar  to  those  at  Maikop.  The 
specific  gravity  of  the  oil  was  0.840  to  0.865.  Another  small  pool  was 
opened  by  Tweddle  in  the  early  eighties,  by  the  river  II,  with  production 
from  both  the  oil  sand  and  the  overlying  Chokrakian,  the  latter  being 
a  heavy  oil. 

Berekei. — Here  a  much  faulted  anticline  occurs  involving  much  the 
same  horizons  as  at  Maikop,  but  oil  occurs  in  many  horizons  and,  being 
associated  with  hot  water,  may  come  from  some  depth.  Its  specific 
gravity  is  0.868. 

Cheleken. — The  actual  productive  area  is  in  the  southwest  corner  of 
the  island,  where  there  is  a  dome  with  its  major  axis  northwest,  but  with 
dips  southwest  of  15°  to  50°  and  northeast  of  18°  to  20°.  It  is  much 
faulted  parallel  to  the  axis  and  the  steep  side  is  involved  in  a  trough 
fault,  whence  the  best  production  of  late  years  has  been  obtained.  The 
dome  itself  has  produced  for  many  years.  Toward  the  center  of  the 
island,  the  larger  dome  of  Chokrak  has  many  oil  indications  but  the 
productive  Pliocene  beds  have  been  denuded  and  the  underlying 
continental  formation  of  unknown  age  is  exposed. 

Emba. — Here  the  surface  is  entirely  covered  by  Pleistocene  beds 
and  the  subsoil  structure  can  only  be  explored  by  the  drill.  Salt  masses 
occur  and  the  detailed  geology  has  not  yet  been  worked  up. 

Ferghana. — The  Syr-Darya  (Jaxartes)  valley  is  a  Cretaceous-Tertiary 
basin  lying  between  the  western  continuation  of  the  Tienshan  mountains 


30  OIL   FIELDS   OF  RUSSIA 

and  the  Zarafshan-Chain.  Oil  indications  occur  in  the  margins  of  the 
Cretaceous  rocks  and  are  associated  with  rather  complex  secondary 
anticlinal  structure  often  partly  concealed  by  Pleistocene  rocks.  The 
worked  fields  of  Chimion  are  on  the  southern  margin. 

DRILLING  OPERATIONS 

Owing  to  the  highly  disturbed  and  unconsolidated  sediments  in  the 
Baku  oil  fields  it  has  been  found  impossible  to  adopt  the  standard 
American  cable  system  or  even  the  rotary.  The  need  for  wells  having 
exceptionally  large  initial  and  completed  diameters  is  due  to  the  neces- 
sity of  excluding  waters  and  penetrating  swelling  and  caving  ground 
during  progress,  as  well  as  to  permit  of  the  extraction  of  oil  by  bailers; 
consequently,  the  "  stove-pipe "  system  is  mostly  employed.  Initial 
diameters  of  36  to  40  in.  (91  to  101  cm.)  are  usual  when  ultimate  diam- 
eters of  12  to  14  in.  are  desired  at  a  depth  of  2000  ft.  Massive  surface 
gear  is  necessary  to  manipulate  columns  of  such  size  and  tools  of 
such  weight.  Engines  or  motors  of  50  to  60  hp.  are  usually  employed  to 
drive  the  rigs. 

Because  of  the  enormous  volume  of  sand  expelled  or  raised  with  the 
oil,  the  drilling  difficulties  of  the  Baku  oil  fields  rather  increased  with  the 
development  of  the  field,  thereby  neutralizing  the  favorable  influence 
of  natural  improvements  that  were  gradually  introduced.  Usually 
from  1  to  3  years  were  occupied  in  drilling  the  deeper  wells,  and  their 
cost,  in  pre-war  days,  was  not  less  than  $25  a  foot;  nearly  50  per  cent, 
of  this  sum  was  for  the  casing  alone. 

Amid  such  disturbed  and  loose  sediments,  no  water-flush  system 
was  permissible  as  the  water  freely  entered  partly  exhausted  sands  and 
found  access  to  all  surrounding  wells,  from  which  it  was  bailed.  Away 
from  the  old  fields,  as  at  Surakhany,  where  a  considerable  thickness  of 
more  consolidated,  non-petroliferous  (or  slightly  so)  beds  have  to  be 
penetrated  before  the  normal  loose,  oil-yielding  facies  is  reached,  rotary 
drilling  has  proved  successful  and  greatly  accelerated  progress  has  been 
made. 

The  system  in  vogue  is  the  free-fall  which,  being  operated  by  rods 
from  the  walking  beam,  transmits  a  positive  action  to  the  drill,  enabling 
tools  to  be  rotated  against  a  resistance  and  the  motion  of  underreamers 
to  be  positive.  Wire-rope  cable  drilling  has  been  successfully  performed 
in  the  Baku  oil  field  under  skilled  direction,  but  the  risks  are  great  and 
the  ultimate  speeds  never  exceeded  those  of  the  free-fall  drilling  system. 
Rarely  could  more  than  a  few  feet  be  left  unlined  without  danger,  and 
often  70  per  cent,  of  the  time  was  occupied  in  the  maintenance  of  the 
freedom  of  the  column  of  casing  to  insure  its  descent  of  only  a  few  hundred 
feet. 


A.  BEEBY  THOMPSON  AND  T.  G.  MADGWICK  31 

Unlike  Baku,  the  Grozny  strata  are  much  more  compact,  and  al- 
though many  of  the  productive  beds  are  unconsolidated  sands  which  are 
freely  expelled  with  the  oil,  the  intervening  beds  hold  up  sufficiently  to 
permit  the  employment  of  standard  wire-line  cable  drilling,  consequently 
quicker  work  results.  The  pre-war  cost  of  wells  3000  ft.  deep  did  not 
exceed  $12  per  ft.,  of  which  about  50  per  cent,  was  for  the  casing.  In 
the  Ural-Emba  oil  field,  where  great  thicknesses  of  gypsum  and  salt  have 
been  pierced  and  the  ordinary  sediments  are  fairly  consolidated,  the 
rotary  drill  has  proved  highly  successful. 

Many  of  the  companies  operating  in  the  Maikop  oil  field  used  the  old 
free-fall  system,  others  used  Galician  rigs,  but  in  the  shallow  field  portable 
Star  rigs  were  found  to  accomplish  just  as  fast  work  as  the  others,  while 
making  unnecessary  the  use  of  expensive  derricks,  and  lengthy  dismant- 
ling and  re-erection  of  plant  on  the  completion  of  each  well. 

Cheleken  conditions  resemble  those  of  Baku  and  wells  entail  long  and 
costly  work  to  complete. 

The  main  feature  distinguishing  Russian  from  American  practice 
is  the  design  and  employment  of  positive  tools,  owing  to  the  great  diffi- 
culties of  dealing  with  loose  sediments  and  the  enormous  financial  losses 
sustained  by  the  abandonment  of  a  well  that  has  required  several  years 
to  make  and  on  which  perhaps  $50,000  or  more  has  been  expended.  Of 
exquisite  design  and  workmanship,  many  of  the  fishing  tools  cost  thou- 
sands of  dollars,  and  they  were  invariably  used  on  solid  or  hollow  fishing 
rods,  which  permitted  the  most  delicate  handling  and  certain  release  if 
they  failed  in  their  object.  All  fishing  rods  had  a  loose  collar  joint  and 
feather  so  that  they  could  be  rotated  right-  or  left-handed  at  will;  reliance 
was  never  placed  on  a  trip  movement,  as  is  the  case  with  many 
American  fishing  tools.  Owing  to  the  heaving  nature  of  the  beds,  it  was 
often  essential  to  employ  powerful  water  flushes  to  free  the  material 
around  a  lost  bit;  for  this  purpose  3-in.  pipes  were  customary. 

The  enforced  use  of  riveted  stove-pipe  casing  rendered  cementations 
for  water  exclusion  lengthy  and  delicate  operations,  as  the  failure  to  hold 
water  or  resist  pressure  without  leakage  prevented  the  simpler  American 
circulation  systems  from  being  adopted.  Anything  beyond  a  shoe  cemen- 
tation made  it  imperative  to  fill  the  casing  with  earthy  matter  and  its 
subsequent  extraction  was  often  as  difficult  as  drilling  a  new  well  in 
most  countries. 

PRODUCTION  METHODS 

During  the  early  history  of  the  Baku  oil  field,  practically  all  wells 
penetrating  a  virgin  sand  body  of  any  importance  flowed  so  violently 
that  their  effective  control  was  practically  impossible.  Enormous 
masses  of  sand  mixed  with  boulders  and  pieces  of  rock  were  often  ejected 
for  days  and  weeks,  rendering  approach  to  the  well  dangerous.  Single 


32  OIL   FIELDS   OF   RUSSIA 

wells  have  given  for  weeks  as  much  as  10,000  tons  daily  of  sand  mixed 
with  an  equal  weight  of  oil,  and  all  objects  placed  to  obstruct  or  deflect 
discharge  were  destroyed  or  perforated  in  a  few  hours.  Usually  hard- 
wood blocks  or  chilled,  cast-iron  plates,  12-in.  thick,  were  pushed  over  the 
mouth  of  the  well  some  distance  above  the  ground,  and  the  vertical  jet 
was  thereby  deflected  horizontally.  These  "  fountain  shields, "  as  they 
were  termed,  were  replaced  as  they  became  destroyed. 

The  wells  themselves  did  not  escape  damage  as  the  casing  was  often 
torn  to  shreds,  each  soft  rivet  causing  the  initiation  of  a  vertical  rifling 
that  extended  upwards  as  the  sand-blast  action  continued.  In  certain 
regions,  when  excessive  gas  pressures  were  encountered,  well  after  well 
was  sunk  and  destroyed  after  a  few  days,  eruption  before  the  pressure 
was  relieved  sufficiently  to  permit  normal  development.  Occasionally, 
sand  only  or  oil-soaked  clay  would  be  expelled  for  days,  or  even  weeks, 
before  oil  entered  or  deepening  could  be  resumed.  On  the  cessation  of 
flowing,  the  wells  were  often  in  a  delicate  condition  and  remunerative 
yields,  free  from  water  that  entered  the  damaged  casing,  could  only  be 
secured  by  the  maintenance  of  a  high  head  of  oil  that,  usually,  exceeded 
the  static  head  of  upper  water  sources.  Such  a  condition  could  only  be 
effected  by  keeping  the  well  clear  of  sand  at  the  bottom  and  so  facilitating 
the  entry  of  oil.  A  little  water  that  practically  always  gained  admission 
nd  collected  near  the  base  of  the  well  not  only  served  to  compact  the 
sand,  but  greatly  impeded  the  entrance  of  oil;  consequently,  the  water 
had  to  be  abstracted  at  regular  intervals.  The  only  method  of  handling 
such  a  condition  was  by  bailing,  and  the  scientific  application  of  this 
principle  reached  a  high  degree  of  efficiency  in  the  Russian  oil  fields. 

Bailing  drums  16  ft.  in  circumference  were  driven  by  engines  develop- 
ing up  to  150  hp.  each,  and  velocities  of  1500  ft.  per  min.  were  common. 
Single  bailers  up  to  7.5  bbl.  capacity  were  used  in  large-diameter  wells 
of  great  yields  and  productions  up  to  2000  bbl.  daily  were  raised  by  this 
method.  The  mean  cost  of  bailing  Baku  wells  in  pre-war  days,  averaging 
120  bbl.  a  day  each,  was  under  20  c.  per  bbl.  but  the  large  yielding  wells 
individually  would  cost  but  a  fraction  of  this  to  bail. 

The  only  other  process  for  raising  oil  that  met  with  success  under  the 
early  Baku  conditions  was  the  air-lift.  In  wells  of  small  diameter  with  a 
high  level  of  liquid  where  bottom  bailing  had  to  be  frequent  to  remove 
water  and  sand  accumulations,  the  air-lift  proved  very  successful.  Al- 
though the  cost  of  operating  the  air-lift  greatly  exceeded  that  of  bailing, 
the  excess  costs  were  often  repaid  many  times  by  the  augmented  yield. 
Emulsions  in  some  cases  gave  trouble,  but  usually  sandy  water  and  oil 
were  alternately  discharged  at  more  or  less  regular  intervals  during  con- 
tinuous or  intermittent  working  as  the  case  might  be.  In  low-level 
wells  all  discharges  were  intermittent  in  operation;  in  high-level  wells, 
the  discharge  was  continuous. 


A.   BEEBY   THOMPSON   AND   T.    G.    MADGWICK  33 

With  the  gradual  reduction  of  gas  pressure  on  the  Baku  oil  fields, 
opportunities  arose  for  the  use  of  pumps  in  the  less  sandy  wells,  but  the 
constant  need  for  renewals  of  cup  leathers,  barrels,  or  plungers  has  caused 
the  system  to  be  unpopular.  The  oil  is  never  quite  free  from  sand  and, 
as  the  density  of  the  oil  is  light  and  sand  quickly  sinks  in  the  column,  there 
is  a  tendency  for  the  plunger  and  valve  to  become  choked  up  if  left  idle 
for  a  few  minutes. 

There  are  fewer  objections  to  the  use  of  pumps  in  most  of  the  other 
oil  fields  of  Russia  but  while  the  period  of  intermittent  flowing  continues 
bailing  is  preferred  in  order  to  keep  the  well  clear  of  sand.  Deep  well 
pumps  are  used  in  the  Grozny  and  other  fields  when  the  wells  have  settled 
down. 

OIL-FIELD  YIELDS 

The  Baku  oil  fields  are  by  far  the  richest  yet  discovered.  Not  merely 
are  the  loose  uncemented  sands  capable  of  high  absorption,  but  they  are 
plentifully  distributed  throughout  a  depth  of  several  thousand  feet  of 
sediments  and  often  reach  a  considerable  thickness.  Thus,  within  the 
confines  of  a  single  plot,  a  dozen  highly  productive  sands  may  be  struck 
aggregating  several  hundred  feet  in  thickness.  A  selected  plot  at  Bibi- 
Eibat  has  yielded  nearly  2,500,000  bbl.  per  acre,  and  the  whole  operated 
area  of  250  acres  in  that  field  has  produced  over  1,500,000  bbl.  per  acre. 
Even  the  greater  Balakhany-Saboontchy  field  of  Baku,  aggregating  about 
2600  acres,  has  yielded  fully  500,000  bbl.  per  acre  and  is  still  capable  of 
enormous  collective  production,  though  the  individual  output  of  wells  is 
now  small.  Enough  oil  has  been  abstracted  from  this  field  to  cover  the 
whole  area  to  a  depth  of  63  ft.  neglecting  entirely  the  many  millions  of 
cubic  feet  of  gas  with  its  contained  gasoline  that  has  been  lost. 

The  influence  of  interference  and  the  process  of  exhaustion  is,  perhaps, 
best  illustrated  by  the  steady  decline  of  initial  productions  of  new  wells. 
Between  1892  and  1896,  the  first  half  yearly  output  of  new  wells  was 
around  108,000  bbl.  (600  bbl.  per  day).  In  1912,  this  had  fallen  to 
15,000  bbl.  (80  bbl.  per  day)  and  during  the  same  interval  the  ultimate 
yield  had  sunk  from  675,000  bbl.  per  well  to  about  225,000  bbl.  In 
1895,  the  average  annual  production  of  wells  at  Baku  was  75,000  bbl.; 
in  1909,  the  average  had  been  depressed  to  30,000  bbl.  although  in  the 
same  period  wells  were  on  an  average  60  per  cent,  deeper.  In  the  Bibi- 
Eibat  field,  footage  ceased  to  increase  or  even  sustain  production  after 
1904  when  the  zenith  of  production  was  attained  in  that  region. 

Civil  disturbances  for  some  years  prior  to  the  war  and  general  dis- 
organization since  make  any  estimates  and  predictions  of  little  value. 
The  fields  are  still  capable  of  giving  enormous  quantities  of  oil,  and  their 
present  potential  capacity  is  probably  between  25,000,000  and  20,000,000 
bbl.  a  year.  Much  local  speculation  is  aroused  as  to  the  results  that  will 

VOL.  LXV. 3. 


34  OIL   FIELDS   OF  RUSSIA 

attend  the  drilling  of  reclaimed  plots  in  Bibi-Eibat  bay,  the  Great  Lake 
of  Romany,  and  large  reserved  areas  surrounded  by  old  producing  plots. 

An  unusual  amount  of  scientific  interest  surrounds  the  obsequies  of 
these  famous  Baku  fields,  and  it  would  be  a  world's  loss  if  trustworthy 
data  were  not  kept  for  the  benefit  of  our  successors.  The  final  phase  is 
apparently  in  sight,  as  what  appears  to  be  basal  water  has  been  pene- 
trated beneath  the  great  oil-bearing  ^series.  Considerable  thicknesses 
of  water-bearing  sands  exist,  but  whether  these  are  underlain  by  other 
oil-bearing  sands  it  is  difficult  to  say.  One  would  surmise  not,  and  there 
is  just  the  possibility  that  the  upper  riches  may  be  partly  due  to  the  ex- 
pulsion of  the  former  oil  contents  of  these  beds  by  water. 

At  present,  the  dregs  of  these  vast  oil  fields  are  being  mainly  secured 
through  the  medium  of  water  which  has  percolated  into  the  disrupted 
and  badly  disturbed  beds  from  which  sufficient  solid  matter  alone  has 
been  flung  by  thousands  of  wells  to  raise  the  oil-field  surface  many  feet. 
From  the  thousands  of  wells  a  mixture  of  oil  and  water  is  constantly 
being  raised,  but  both  the  oil  and  the  water  contents  are  being  reduced. 
Some  areas  no  longer  yield  water  at  all  where  formerly  expensive 
measures  had  to  be  undertaken  for  its  exclusion;  here  the  least  oil  is  now 
obtained  as  natural  filtration  without  the  aid  of  gas  or  water  is  in- 
significant. At  other  points  the  static  head  of  the  liquid  is  gradually 
falling,  and  unless  the  lower  water  is  admitted  the  whole  field  may  be 
eventually  dried  up.  No  synclinal  or  edge  water  that  cannot  be  over- 
come by  bailing  encroaches  on  the  exhausted  upper  oil  strata,  so  that 
the  chief  migration  of  oil  may  have  been  vertical  rather  than  lateral. 

The  Surakhany  field  to  the  east  of  the  Balakhany-Saboontchy  area 
has  now  become  the  most  interesting  in  the  Baku  zone.  Years  ago,  the 
deep  development  of  the  oil  series  was  predicted  by  geologists  and  their 
predictions  have  been  verified.  Enormous  volumes  of  natural  gas  were 
obtained  from  shallow  fine  sands  in  the  area  and  the  product  was  piped  to 
the  oil  fields  for  fuel.  At  increased  depths,  gushers  of  white  oil,  specific 
gravity  0.785,  were  struck  in  similar  sands,  and  there  is  now  little  doubt 
that  they  represented  a  filtration  product  of  migration  from  the 
underlying  normal  series. 

Large  gushers  of  the  typical  Baku  grade  oil  have  been  struck  in  the 
Surakhany  area  where  an  active  development  was  in  progress  until  the  war. 

In  the  Grozny  oil  field,  wells  have  given  very  substantial  productions 
along  a  belt  of  many  miles.  No  area  has  excelled  in  productivity  the 
original  plot  on  which  the  first  well  was  drilled,  about  1897.  This  point 
corresponded  with  the  maximum  elevation  on  the  pitching  anticline  and 
attracted  attention  by  its  surface  manifestations.  This  plot  has  yielded 
over  320,000  bbl.  of  oil  per  acre.  In  1914,  Grozny  yielded  10,500,000  bbl. 
from  about  8000  acres.  The  field  has  given  about  150,000  bbl.  per 
acre  and  is  still  far  from  exhausted.  After  an  initial  flow,  wells  continue 


A.  BEEBY  THOMPSON  AND  T.  G.  MADGWICK  35 

to  yield  normally.  A  typical  well  yielding  an  ultimate  production  of 
80,000  bbl.  gives  about  50  per  cent,  of  its  total  production  in  the  first 
year,  22  per  cent,  in  the  second,  15  per  cent,  in  the  third,  and  1%  per 
cent,  in  the  fourth. 

Exceptionally  good  results  were  obtained  on  the  Bellik  oil  field, 
discovered  in  1912.  It  is  really  an  extension  of  the  old  Grozny  oil 
field  or  a  parallel  fold.  Pioneer  wells  gave  large  and  sustained  flows, 
and  an  important  field  is  likely  to  result,  possessing  the  Grozny 
characteristics. 

No  detailed  statistics  are  available  concerning  the  important  Emba 
oil  field  of  the  Uralsk.  Large  flowing  wells  were  struck  in  some  number 
near  Dossor  and  considerable  shipments  of  oil  were  made  to  the  Volga. 
There  is  every  indication  of  a  large  and  useful  field  being  opened  up. 
The  Island  of  Cheleken,  off  Krasnovodsk,  gave  its  maximum  output  in 
1912,  when  1,500,000  bbl.  were  reported.  In  1913,  the  production  was 
under  1,000,000  bbl.  and  the  fall  continues.  Activity  was  confined  to  the 
Ali  Tepe  sector,  which  area  seems  to  have  passed  its  best  days.  Holy 
Island  has  attracted  sporadic  attention  and  appears  to  justify  more. 
One  company  operates  and  produces  about  800,000  bbl.  a  year  when 
conditions  are  normal. 

The  small  field  near  Shirvansky,  known  as  the  Maikop,  has  yielded 
over  4,000,000  bbl.  of  oil;  a  production  of  about  250,000  bbl.  a  year  is 
still  maintained  despite  the  fact  that  the  area  has  not  been  greatly 
extended. 

Little  information  is  forthcoming  about  Ferghana  oil  field  of  Turkes- 
tan. At  one  time  the  production  reached  450,000  bbl.  a  year  and  the 
oil  found  a  ready  local  sale  in  that  part  of  the  world.  At  Maili  Sai,  no 
further  drilling  has  been  undertaken. 

Innumerable  abortive  or  uncertain  tests  have  been  made  in  the 
Caucasian  oil  belt.  Some  were  undertaken  at  a  time  when  nothing 
short  of  500-bbl.  wells  attracted  any  interest  at  all.  At  many  spots  produc- 
tions have  been  obtained  that  would  pay  well  in  any  other  part  of  the 
world.  All  along  the  Caspian  Sea  littoral,  from  Baku  to  Derbent, 
there  are  frequent  and  encouraging  indications  of  oil.  At  Berekei,  a 
little  northwest  of  Derbent,  about  500,000  bbl.  of  oil  were  taken  from  a 
field  in  which  2000-  to  5000-bbl.  wells  were  struck;  but  water  troubles 
eventually  drove  away  nearly  all  operators.  At  Kaikent,  a  large  gusher 
was  struck  in  an  initial  effort,  although  all  subsequent  wells  failed. 
Around  Baku  at  Binagadi,  a  much  despised  region  left  for  years  to  peas- 
ants to  develop  by  primitive  methods  gave,  in  1913,  1,750,000  bbl.  of 
oil  and  has  since  exceeded  4,000,000  bbl.  a  year.  At  Puta  and  Kharda- 
lan,  a  thriving  industry  developed  as  a  result  of  hand-dugs  sunk  into 
the  outcropping  oil  sands  and  an  output  of  1,700,000  bbl.  resulted  in 
1914.  Drilling  would  yield  very  different  results. 


36  OIL   FIELDS   OF   RUSSIA 

Miles  of  territory  flanking  the  Caucasus  foot-hills  that  fringe  the 
valley  of  the  Kura  are  capable  of  remunerative  development.  In  some 
places  small  wells,  still  flowing,  testify  to  past  efforts,  and  at  many  places 
the  peasants  satisfy  all  local  wants  by  sinking  shafts  into  outcropping 
oil  sands. 

At  Ildohani  in  the  Tionct  valley,  near  Tiflis,  productive  wells  were 
sunk  that  flowed  oil  of  light  density  in  which  crystals  of  wax  separated; 
at  other  places  in  the  same  district  fruitless  experiments  were  made  with 
antiquated  plants  where  modern  methods  might  have  succeeded.  At 
Chatma,  near  the  River  Jora,  there  are  numerous  indications  of  oil  and 
interesting  structures. 

Miles  of  the  Black  Sea  littoral  and  Taman  peninsula  are  potential 
oil  fields;  indeed,  many  dozens  of  productive  wells  have  been  sunk  in 
that  region  where  such  stupendous  mud  volcanoes  are  in  evidence. 
Russian  geologists  have  estimated  that  there  are  fully  30,000  sq.  mi. 
of  interesting  undeveloped  oil  land  in  Russia  and  this  is  probably  no 
exaggeration. 

CHIEF  RUSSIAN  OIL  FIELDS 

The  main  oil  fields  of  Russia,  in  the  order  of  their  relative  importance, 
are  as  follows : 

APPROXIMATE        APPROXIMATE 
PRODUCTION,        PROVED  AREA, 
IN  BARRELS  ACRES 

Balakhany-Saboontchy  field,  | 

Romany, V  to  1918  1,597,690,000  J        2,600 

Bibi-Eibat  field, J  1,000 

Surakhany  field,  to  1918 54,920,000 

\   '    I  to 
ik  field, ) 

Binagadi,  to  1918 22,620,000 

Khurdalan  ^ 

Puta  I  to  1917 9,082,000 

Berekei         J 

Holy  Island,  to  1918 5,562,000 


—    So 

oj  U      Dossor,  etc.,  to  1917  ......  8,575,000 


=  i 

0)   *S 

J3  3  Cheleken  Island,  to  1917  ....................         7,317,000 

I  c  Ferghana  field,  to  1917  ......  ...............         3,620,000 


Maikop,  to  1917  ...........................         4,750,000 


Baku 


I 
\ 


Grozny  {  to  1917 Lttd . . . . . .  -     139,858,000         8,000 


DISCUSSION 


37 


TABLE  4. — Approximate  Production,  in  Thousands  of  Barrels  (8.3 

Poods  to  a  Barrel) 


Previous  to 
1914 

1914 

1915 

1916 

1917 

1918 

Baku  Oil  Fields 
Balakhany-Saboontchy 
Romany 

1 

|  1,427,950 

12,400 
7,380 
1,980 
5,300 

|     93,800  { 

845 
2,870 

5,670 
2,680 

132,000 

8,700 
6,200 
2,650 
712 
840 

10,600 
1,028 

2,000 
482 

602 
217 

31,800 

9,550 
7,270 
3,930 
844 
930 

9,260 
1,350 

1,990 
915 

482 
241 

29,000 

10,800 
11,600 
4,160 
820 
1,180 

8,280 
4,100 

1,870 
241 

362 
241 

24,600 

7,350 
11,150 
3,560 
844 
832 

6,620 
4,820 

1,870 
242 

201 
241 

12,500 

3,440 
6,300 
940 
362 

5  gushers 
burning  9 
months 

Bibi-Eibat  

Surakhany 

Binagadi  

Holy  Island  .  .  . 

Khurdalan,  Puta,  etc.  .  . 
Terek 
Grozny  field 

Bellik  field  

North  Caspian 
Emba  oil  field 

Kuban 
Maikop 

Asiatic  Russia 
Cheleken       

Ferghana  

DISCUSSION 

ARTHTJK  KNAPP,  Shreveport,  La. — From  this  paper  one  would  be 
led  to  believe  that  the  American  system  of  drilling  was  not  a  success  in 
Russia;  I  spent  two  years  in  the  Baku  field  and  know  that  this  is  not  true. 
The  first  rotary  rig  that  I  know  of  was  sent  over  there  in  1913.  The 
Russian  engineers  were  so  opposed  to  the  use  of  the  rotary  that  it  was  not 
until  1914  that  a  well  was  drilled  using  American  methods  throughout. 

The  first  rotary  hole  was  drilled  1800  ft.  (548  m.)  in  about  three 
months  and  offset  a  well  that  took  2J^  years  to  drill  by  the  Russian 
method.  The  Russian  method  used  about  120  tons  of  casing  while  the 
American  method  used  only  two  strings,  10  and  6  in.,  with  a  saving  of 
from  $75,000  to  $80,000.  During  the  next  two  years,  between  eighteen 
and  twenty  rotary  wells  were  finished  in  the  field.  In  every  case  there 
was  a  saving  of  from  20  to  60  per  cent,  on  casing  and  from  30  to  50  per 
cent,  on  time  and  labor. 

The  fundamental  difference  between  the  Russian  and  American 
systems  of  producing  oil  is  that  in  America  we  try  to  keep  the  oil  for- 
mation from  moving,  by  the  use  of  screens,  where  necessary,  while  the 
Russian  engineer  does  everything  he  can  to  produce  a  large  quantity  of 
sand.  The  drilling  with  the  rotary  is  about  the  same  as  the  drilling  in 
the  Midway  field  in  California. 


38  OIL   FIELDS   OF  RUSSIA 

The  Russian  engineers  have  opposed  the  use  of  deep  well  pumps  as 
a  means  of  producing  oil.  I  installed  an  ordinary  2-in.  pump  in  a  well 
that  produced  about  12  bbl.  of  oil  and  increased  the  production  to  24  bbl. 
on  the  beam.  Our  statistics  showed  a  saving  of  50  per  cent,  over  bailing. 
Another  company  under  English  control  put  about  twelve  wells  to 
pumping  on  jacks.  They  were  run  for  some  time  and  the  cost  compared 
with  the  same  kind  and  number  of  wells  being  produced  by  bailing.  The 
pumping  wells  used  about  25  per  cent,  of  the  steam  that  was  required  by 
the  bailing  wells.  The  labor  costs  were  12  per  cent,  and  the  repairs  and 
upkeep  5  per  cent,  of  the  bailing  costs. 

The  deepest  wells  in  the  Baku  fields  at  the  time  that  I  was  there 
were  about  3000  ft.  deep.  They  took  at  least  three  years  to  drill  by  the 
Russian  system  and  cost  about  $125,000.  Only  one  out  of  three  of  the 
Russian  wells  at  this  depth  was  a  successful  producer.  The  uniform 
success  of  the  American  system  was  very  much  in  its  favor.  Out  of  the 
fifteen  or  twenty  wells  drilled  during  1914-15,  only  two  of  the  American 
wells  were  lost. 

The  American  rotary  system  is  being  very  rapidly  adopted.  When 
the  war  stopped  imports  the  Russians  tried  with  good  success  to  make 
rotaries  of  their  own.  The  rotary  may  never  entirely  supplant  the 
Russian  rig  but  it  has  been  a  great  success  and  has  come  to  stay  in 
Russia. 

Mr.  Thompson's  paper  is  the  only  one  that  I  know  of  that  brings 
our  knowledge  of  the  Russian  oil  fields  up  to  date.  It  is  a  valuable 
addition  to  our  literature. 

A.  BEEBY  THOMPSON  (author's  reply  to  discussion). — Mr.  Arthur 
Knapp's  remarks,  without  some  qualification,  are  apt  to  be  misleading. 
In  the  past,  the  leading  oil  companies  of  Baku  have  spent  large  sums  in 
experimenting  with  American  plant  and  have  offered  high  rewards  to  any 
successful  operator  who  could  increase  speeds  and  reduce  costs  but  a  small 
percentage.  The  best  operators  were  sought  and  every  facility  granted 
them  but  until  just  before  the  war  no  improved  results  had  been  achieved; 
indeed,  until  the  modern  heavy  type  rotary  was  introduced  the  problem 
appeared  hopeless.  Any  driller  who  could  have  saved  but  20  per  cent,  in 
time  or  costs  of  drilling  wells  in  the  rich  Baku  oil  field  could  have  made 
contracts  that  would  have  yielded  him  a  fortune  in  a  few  years,  as  the 
time  factor  in  such  congested  areas  meant  so  much  to  operators.  Where 
wells  are  drilled  within  100  ft.  or  less  of  each  other  and  a  few  square  miles 
are  perforated  by  thousands  of  wells,  it  is  almost  inconceivable  that 
rotary  flush  drilling  could  be  uniformly  successful,  for  the  mud  enters  the 
loose,  partly  exhausted  sands  and  follows  channels  of  flow  to  neighboring 
producing  wells.  Attempts  in  Bibi-Eibat  many  years  ago  caused  many 
wells  to  turn  to  mud  and  water  when  the  rotary  penetrated  one  of  the 
main  sands  from  which  the  wells  were  drawing  oil. 


DISCUSSION  39 

Rotary  drilling  has  proved  successful  only  in  areas  outside  the  con- 
gested fields  where  great  thicknesses  of  uninteresting  beds  have  to  be 
pierced  before  the  productive  oil  series  is  reached  or  where  oil  occurs  in 
more  compacted  strata.  Any  operator  able  to  save  $75,000  worth  of 
casing  and  nine-tenths  of  the  time  of  drilling  in  proved  areas  could  within 
a  few  years  be  a  wealthy  man. 

The  Russian  engineers  have  not  opposed  pumping  on  principle,  as  in 
Grozny  and  Maikop  pumping  has  been  conducted  for  years.  As  far 
back  as  1900,  the  writer  made  persistent  efforts  to  use  pumps  in  the  Baku 
oil  fields  but  the  large  quantities  of  sand  accompanying  the  oil  made  their 
use  impossible.  In  no  case  could  a  highly  productive  well  be  pumped  for 
more  than  a  few  hours  without  the  pump  being  choked  by  sand  and  the 
cups  or  plungers  being  cut  to  pieces.  Induced  flows  through  the  pump 
sometimes  brought  in  sufficient  quantities  of  sand  to  fill  hundreds  of  feet 
of  the  tubing.  At  that  time  no  12  or  24  bbl.  well  was  accepted  and  prob- 
ably 100  bbl.  was  the  minimum  payable  yield.  Conditions  are  quite 
different  today  and  there  are  many  Baku  properties  where  the  slowly 
infiltrating  oil  is  sufficiently  free  from  sand  to  enable  grouped  pumping  to 
be  conducted.  In  the  past,  the  output  of  a  well  fell  off  to  an  unpayable 
yield  unless  the  sand  that  entered  the  well  was  constantly  being  removed, 
by  bottom  bailing. 


40  PETROLEUM   IN   THE   ARGENTINE   REPUBLIC 


Petroleum  in  the  Argentine  Republic 

BY  STANLEY  C.  HEROLD,*  TULSA,  OKLA. 

(New  York  Meeting,  February,  1920) 

AT  THE  present  time  five  localities  in  the  Argentine  Republic  are 
known  to  bear  direct  evidences  of  the  presence  of  petroleum.  The 
segregation  of  these  localities  is  more  or  less  arbitrary  inasmuch  as  minor 
indications  may  be  found  to  extend  from  one  locality  to  the  other  at  no 
regular  distance  apart,  especially  in  the  northern  and  western  part  of  the 
republic.  These  localities  are  listed  as  follows:  North  Argentine-Bo- 
livian region,  Salta-Jujuy  district,  provinces  of  Mendoza  and  Neuquen, 
Comodoro  Rivadavia,  and  the  Gallegos-Punta  Arenas  region. 

Economic  conditions  attract  us  to  the  possibilities  of  developing  these 
and  other  regions  of  countries  in  the  southern  hemisphere.  Develop- 
ment work  will,  naturally,  be  undertaken  first  in  such  localities  as  present 
direct  manifestations  of  the  presence  of  petroleum;  "hidden  fields" 
may  exist,  but,  unless  discovered  by  accident,  their  development  will  be 
left  to  the  last. 

The  problems  to  be  solved  in  the  development  of  the  petroleum 
resources  of  the  Argentine  republic  are  mainly  of  stratigraphy,  structure, 
and  transportation.  We  are  not  here  concerned  with  the  unfavorable 
climate  of  the  countries  to  the  north  in  the  tropics  where,  for  us  of  the 
"far  north,"  life  hangs  by  a  thread  ready  to  be  severed  by  a  mosquito, 
gnat,  or  tropical  germ. 

NORTH  ARGENTINE-BOLIVIAN  REGION 

The  North  Argentine-Bolivian  region  has  already  been  described  by 
the  author.1  Geographically  and  geologically  this  is  admittedly  one  field 
extending  from  Argentine  into  Bolivia.  It  is  not  necessary  to  repeat 
here  the  various  conditions  pertaining  to  this  field,  though  the  summary 
may  be  quoted  as  follows: 

Extending  from  northern  Argentine  northward  into  central  Bolivia  is  a  belt  of 
petroleum  seepages.  On  account  of  the  remoteness  of  the  district  it  has,  heretofore, 
been  little  considered  by  oil  operators.  The  regional  geology  is  comparatively  well 
understood  but  the  local  features  have  not  been  carefully  detailed. 

Development  work  in  the  past  has  been  done  on  an  unscientific  basis  and  has  led 
to  failures.  At  the  present  time,  access  to  the  region  is  somewhat  difficult  but  no 

•Chief  Geologist,  Tulsa  District,  Sinclair  Oil  and  Gas  Co. 
i  Trans.  (1919)  61,  544. 


STANLEY   C.    HEROLD  41 

serious  problem  would  be  encountered  in  improving  the  conditions.  The  nearest 
railroad  terminal  is  at  Embarcaci6n,  114  mi.  (183  km.)  south  of  the  Bolivian  border, 
or  72  mi.  (116  km.)  from  the  nearest  manifestation  of  petroleum  in  natural  springs. 

The  oil  is  of  high  quality  and  the  seepages  occur  in  creek  beds  along  the  Sierra  de 
Aguaragiie  fault,  and  at  other  isolated  places. 

Native  labor  is  good  and  government  policies  are  sympathetic  toward  foreign 
exploitation. 

Though  the  structural  features  of  the  region,  as  a  unit,  have  been  worked  out  by 
reconnaissance  surveys,  there  still  remain  many  local  sections  upon  which  no  detailed 
study  has  been  made. 

Several  small  areas  have  been  proved  unfavorable  for  production,  though  the 
region  as  a  whole  cannot  be  condemned  on  this  account. 

Since  writing  the  above  there  has  been  no  further  development  in  this 
district,  to  the  author's  knowledge,  though  individuals  have  had  their 
geologists  there. 

THE  SALTA-JUJUY  DISTRICT 

The  Salta-Jujuy  district  lies  to  the  west  of  the  foregoing  area,  north- 
west and  north  of  the  town  of  Salta,  extending  into  Bolivia.  There  may 
be  no  logical  reason  for  separating  these  fields  except  that  the  latter  lies 
in  the  mountainous  and  somewhat  inaccessible  part  of  the  country.  The 
stratigraphy  of  one  is  closely  related  to  that  of  the  other.  Seepages  are 
small  and  widely  scattered,  of  high  quality  oil,  and  not  of  continuous 
flow,  for  heavy  rains  may  either  temporarily  efface  or  bring  to  light  slight 
showings  of  petroleum,  depending  on  local  conditions. 

The  structure  of  the  district  is  rather  complex  due  to  the  folding 
and  faulting  of  the  strata  lying  on  the  side  of  igneous  formation  protruded 
in  the  Andes  uplift.  As  the  surface  is  made  up  of  steep  mountains  and 
narrow  gorges  largely,  there  is  small  probability  of  extensive  develop- 
ment. The  seepages  occur  along  the  exposures  of  beds  dipping  at  high 
angle  and  along  faults. 

PROVINCES  OF  MENDOZA  AND  NEUQUEN 

These  two  provinces  lie  on  the  eastern  flank  of  the  Andes  Mountains 
due  west  from  Buenos  Aires  and  adjoining  the  Republic  of  Chile.  The 
province  of  Mendoza  is  traversed  by  the  trans-Andean  railway  which 
extends  from  coast  to  coast.  Seepages,  generally  of  tar  or  asphalt  and 
heavy  oil,  extend  in  a  north-and-south  line  along  the  frontal  ranges,  paral- 
leling the  main  trend  of  the  range.  The  author  made  but  a  casual  observa- 
tion in  this  district  and  is  therefore  not  competent  to  enter  a  detailed 
discussion  of  stratigraphic  conditions.  The  main  features  are  beds  of 
steep  dip  and  numerous  faults.  Some  development  has  been  under- 
taken in  the  past  but  up  to  autumn  of  the  year  1917  no  success  had  been 
met.  The  area  has  its  possibilities. 


42  PETROLEUM  IN  THE  ARGENTINE   REPUBLIC 

COMODORO   RrVADAVIA 

At  Comodoro  Rivadavia  is  situated  the  only  successfully  developed 
oil  field  in  the  Argentine  Republic.  It  is  located  in  the  southeast  corner 
of  the  territory  of  Chubut  along  the  Atlantic  seacoast,  immediately  north 
of  the  town  of  Comodoro  Rivadavia,  on  the  Gulf  of  St.  George  (San 
Jorge)  at  approximately  latitude  south  45°  45'  and  longitude  west  67°  20' 
from  Greenwich.  From  Buenos  Aires,  the  field  lies  in  a  direction  of  south 
30°  west,  1164  mi.  (1875  km.)  distant,  as  the  ships  sail. 

The  area  includes  the  reserved  land  of  the  Argentine  Government  of 
5000  ha.  (12,050  acres),  5000  by  10,000  m.  along  the  coast  covering  the 
town  of  Comodoro  Rivadavia  itself.  Furthermore,  it  includes  various 
areas  adjoining  this  reservation  to  the  north,  west,  and  south.  Three 
properties  were  producing  petroleum  in  the  latter  part  of  the  year  1917: 
namely,  the  government  reservation,  the  Compania  Argentina  de  Como- 
doro Rivadavia,  and  the  Astro  property,  the  latter  situated  about  20 
km.  north.  Many  claims  or  concessions  have  been  taken  up  by  local 
parties,  some  of  which  appear  to  be  favorable  for  production. 

Previous  to  the  accidental  discovery  of  oil  by  drilling  for  water  there 
were  said  to  be  absolutely  no  signs  of  the  existence  of  oil  or  gas  under  the 
surface  in  this  region.  The  domestic  water  supply  of  the  town  of  Como- 
doro Rivadavia  was  very  poor  and  in  such  condition  as  to  render  the 
district  unhealthy.  In  the  year  1908,  the  Argentine  Government  sent  a 
drilling  outfit  there  to  prospect  for  water,  a  site  having  been  chosen 
opposite  the  bank  building  in  town.  No  water  was  encountered  so 
the  drill  was  removed  to  a  place  3]  km.  north.  Drilling  proceeded 
until  a  strong  flow  of  gas  was  encountered  and  later  a  gusher  of  oil  at 
1770  ft.  (540  m.)  below  sea  level.  The  well  was'probably  not  over  70  ft. 
above  the  sea. 

Since  discovery,  drilling  has  been  continued  with  more  or  less  regular- 
ity until,  in  the  latter  part  of  1917,  about  sixty  wells  had  been  put  down 
on  the  reservation,  a  fair  proportion  of  which  proved  successful.  Water 
is  now  brought  from  the  hills  to  the  west  through  pipe  and  supplies  all 
requirements. 

Within  the  government  area,  at  least  three  sedimentary  series  exposed 
at  the  surface  have  been  differentiated.  The  lowest  stratum  exposed  is 
that  of  a  white,  soft,  tufaceous  formation  lying  at  the  base  of  the  hills 
immediately  to  the  north  of  the  oil  field.  Traces  of  carboniferous  matter 
have  been  found  in  this  formation  but  no  fossils  capable  of  recognition 
were  on  record  at  the  time  of  the  author's  visit.  Its  age  was  considered 
to  be  Lower  Eocene  or  possibly  Upper  Cretaceous.  About  50  ft.  of  the 
series  is  exposed. 

The  next  younger  formation  is  a  series  of  sandstones  and  shales. 
The  sandstone  is  light  brown  in  color,  soft,  and  easily  eroded.  Sand 


STANLEY   C.    HEROLD  43 

grains  are  of  medium  size.  Beds  vary  in  thickness  from  10  to  50  ft., 
bedding  planes  well  defined.  The  shale  is  also  light  brown  where  exposed 
and  very  soft.  The  entire  thickness  of  the  series  is  approximately  200  ft. 
Fossils  of  this  formation  were  considered  to  be  of  Eocene  Age. 

The  third  and  youngest  stratified  series  is  the  so-called  "Patagonia" 
series,  a  formation  composed  largely  of  soft,  light  brown,  thinly  bedded 
sandstone.  Some  shale  occurs.  It  is  this  formation  that  stands  in  high 
cliffs  to  the  west  of  the  field.  At  least  300  ft.  of  the  series  is  exposed  in 
the  immediate  vicinity.  Fossils  are  very  abundant.  They  are  prob- 
ably of  Oligocene  age. 

In  addition  to  these  stratified  deposits  there  is  a  great  amount  of 
chert,  water-worn  pebbles  lying  loosely  on  the  ground  above  the  Pata- 
gonia series  and  particularly  along  the  beach.  These  pebbles  are  pre- 
dominantly of  yellow,  red,  green,  and  black  colors  and  undoubtedly 
were  transported  from  a  distance. 

The  formations  below  the  tuff  penetrated  by  the  drill  are  mostly 
gray  shales  and  sandstones,  the  hardness  of  which  varies  somewhat  in 
the  different  strata.  They  may  be  Lower  Eocene  or  Upper  Cretaceous. 

The  beds  at  the  surface  lie  at  a  very  low  angle,  somewhat  similar 
to  conditions  in  the  Mid-Continent  fields.  The  normal  dip  is  toward 
the  southeast  with  sufficient  undulation  to  produce  flat  dome  struc- 
tures with  closures  in  contours  on  the  northwest.  At  the  close  of 
Patagonia  time,  a  gentle  but  extensive  uplifting  took  place  throughout 
the  entire  region,  leaving  the  strata  almost  horizontal,  producing  the 
great  "pampas,"  or  high  plains,  to  the  west  toward  the  Andes.  Evi- 
dently little,  if  any,  lateral  pressure  was  exerted  upon  the  strata,  for 
they  appear  little  disturbed  except  for  their  elevation.  The  sea  and 
rains  have  ravaged  the  coast  line,  leaving  a  shelf  with  low  relief  along 
the  coast;  it  is  on  this  shelf  that  we  find  the  development  of  the  field. 

The  oil  is  found  on  the  above-mentioned  domes  in  a  sand  that  lies 
conformably  to  the  series  at  the  surface  at  a  depth  close  to  530m.  (1740ft.) 
below  sea  level.  The  texture  of  the  sand  seems  to  vary  considerably, 
producing  non-porous  parts  sufficiently  tight  to  exclude  the  oil.  For 
this  reason  oil  is  not  always  encountered  as  soon  as  the  oil  formation  is 
struck.  In  some  wells  it  was  reported  that  oil  was  not  encountered 
until  a  depth  of  580  m.  (1900  ft.)  had  been  reached.  Overlying  the  oil 
series  is  a  soft  bluish-gray  shale.  The  age  of  the  series  was  thought  to 
be  Upper  Cretaceous,  though  this  was  not  certain.  Water  has  been 
encountered  but  no  difficulty  is  experienced  in  shutting  it  off. 

The  wells  of  this  field  have  been  drilled  by  a  combination  of  the  rotary 
drill  to  a  depth  of  462  m.  (1515  ft.)  and  the  Fauck  system  with  rods  to 
the  oil  strata.  The  rigs  are  of  the  closed-in  type,  covered  with  sheet 
iron  on  four  sides  to  the  top.  They  must  be  heavily  guyed  to  prevent 
damage  from  strong  winds  prevailing  during  certain  seasons.  At  the 


44  PETROLEUM   IN   THE   ARGENTINE   REPUBLIC 

time  of  the  writer's  visit,  two  American  rigs  had  recently  been  built  to 
use  cable  tools  in  combination  with  the  rotary  outfit.  As  far  as  they 
had  been  used,  they  were  making  an  admirable  record  compared  with 
the  rods.  It  seems  quite  necessary  to  use  the  rotary  for  the  upper 
part  of  the  hole,  as  the  walls  are  subject  to  caving.  Strong  flows  of 
briny  water  are  encountered  at  350  m.  (1150  ft.)  and  at  435  m.  (1428ft.). 
Gas  is  often  struck  at  150  m.  (492  ft),  and  at  400  m.  (1312  ft.). 

In  August,  1917,  twenty-five  wells  were  producing  4000  bbl.  of  oil 
per  day  and  an  average  of  60  m.  (195  ft.)  of  new  hole  per  day  was  being 
drilled.  The  oil  is  heavy,  about  18°  Be",  on  an  average,  black  in  color, 
with  a  low  content  of  gasoline.  There  is  a  small  refinery  on  the  ground 
for  extracting  the  gasoline.  The  refuse  is  returned  to  the  storage  tanks 
for  shipping  to  Buenos  Aires,  where  it  is  used  by  industrial  plants  as 
fuel.  The  government  maintained  a  fleet  of  four  tankers  at  that  time. 
Loading  was  often  done  with  difficulty  on  account  of  lack  of  harbor 
facilities,  since  the  Gulf  of  St.  George  is  quite  open  to  the  Atlantic. 
Although  but  twenty-five  wells  were  producing,  about  thirty-five  others 
had  been  drilled  and  had  either  been  dry,  lost  holes,  or  abandoned  as  no 
longer  profitable  to  operate.  It  is  understood  that  this  record  has  been 
considerably  improved  since  that  time. 

A  fair  proportion  of  the  territory  can  be  surveyed  in  detail,  as  is 
being  done  in  the  Mid-Continent  field.  The  most  favorable  localities 
may  therefore  be  selected  for  the  drill  with  a  minimum  of  failures. 
Stratigraphic  conditions  are  favorable  for  a  considerable  extension  of 
present  known  producing  area.  Transportation  presents  little  difficulty, 
since  the  field  adjoins  the  sea  and  market  conditions  are  capable  of  great 
expansion;  all  oil  not  needed  by  the  industries  in  Buenos  Aires  may  be 
devoted  to  use  in  oil-burning  vessels,  which  would  call  if  fuel  were  available. 

GALLEGOS-PUNTA  ARENAS  REGION 

At  the  southernmost  section  of  the  continent  is  located  the  Gallegos- 
Punta  Arenas  region.  In  addition  to  the  well-known  gas  springs  near 
the  town  of  Punta  Arenas,  the  manifestations  extend  northward  to  a 
district  due  west  of  the  port  of  Gallegos.  In  the  latter  locality,  the 
streams  are  reported  by  competent  observers  to  be  carrying  small  quanti- 
ties of  crude  oil  toward  Lake  Blanca.  The  author  has  not  studied  this 
region,  so  is  unable  to  give  information  regarding  conditions  and  possi- 
bilities of  development. 

DISCUSSION 

THE  CHAIRMAN  (E.  DEGOLYER,  New  York,  N.  Y.).— The  production 
of  petroleum  in  the  Argentine  is  entirely  in  the  hands  of  the  government. 
Some  years  ago,  in  attempting  to  develop  a  water  supply  for  the 
Patagonian  region,  the  department  in  charge  of  drilling  brought  in  a 


DISCUSSION  45 

gushing  well.  The  president  immediately  withdrew  a  considerable 
reserve  around  this  well;  subsequently,  the  government  reduced  the  size 
of  the  reserve  to  5000  hectares  and  proceeded  to  develop  the  property. 
I  have  studied  several  of  the  reports  of  the  Commission  that  has  the 
matter  in  charge,  and  am  not  able  to  determine  whether  or  not  it  is  a 
profitable  venture  for  the  government,  but  it  seems  to  have  devel- 
oped a  distinct  policy  of  exclusion.  The  mining  laws,  like  the  mining 
laws  in  most  Latin-American  countries,  practically  made  no  provision  for 
petroleum.  They  were  a  development  of  the  old  Spanish  mining  codes 
when  petroleum  was  not  recognized  as  a  mineral.  In  most  of  these 
Latin-American  countries,  some  sort  of  special  legislation  has  been 
required  to  make  it  possible  for  one  to  go  in  to  develop  the  petroleum 
resources.  As  the  tendency  in  the  Argentine  seems  to  be  to  keep  the 
thing  in  the  hands  of  the  government,  there  is  the  peculiar  condition  that 
a  nation  that  has  no  coal  fuel,  and  where  fuel  is  the  utmost  importance, 
seems  to  be  determined  to  have  no  oil  development  either. 

S.  C.  HEROLD  (author's  reply  to  discussion). — At  the  present  time, 
development  work  is  carried  on  in  various  parts  of  the  Argentine  Republic 
by  several  distinct  companies  largely  financed  by  foreign  capital,  though 
one  or  two  have  included  a  fair  proportion  of  local  capital.  While  some 
of  these  operating  companies  have  not  brought  in  producing  wells,  the 
possibilities  are  particularly  good  in  some  instances. 

The  Argentine  Government  now  has  two  reserved  zones;  namely,  that 
referred  to  by  Mr.  DeGolyer  at  Comodoro  Rivadavia  at  the  southeast 
corner  of  the  Territory  of  Chubut  adjacent  to  the  coast  line  along  the 
Gulf  of  St.  George,  and  that  at  Station  Plaza  Huincul  in  the  Territory  of 
Neuquen,  both  of  5000  hectares  area.  It  is  understood  that  a  third  zone 
may  be  set  aside  near  the  Cerro  Negro  region,  Neuquen  Territory.  The 
favored  location  for  work  by  the  private  companies  has  been,  so  far,  near 
the  zones  reserved  by  the  Government.  These  zones,  with  their  adjoin- 
ing lands,  are  within  "Territorial"  jurisdiction;  as  the  territories  are 
controlled  from  the  national  seat  of  government  in  Buenos  Aires,  the 
national  laws  providing  for  petroleum  development  are  the  only  laws 
prevailing.  The  provinces  may  have  their  own  departments  of  mining, 
etc.,  and  may  detail  their  laws  respecting  oil  claims  so  long  as  such  details 
do  not  conflict  with  the  spirit  of  the  national  laws;  within  the  territories 
no  such  detail  can  be  worked  out. 

It  cannot  be  properly  stated  that  there  is  any  intentional  exclusion 
policy  on  the  part  of  the  country.  Any  exclusion  prevailing  is  due  rather 
to  that  which  the  Government  has  failed  to  do  than  to  what  it  has 
done.  We  can  hardly  expect  a  country  that  has  only  reached  the 
stage  of  development  in  petroleum  which  the  Argentine  has  experienced 
to  date  to  have  all  matters  worked  out  in  detail.  Capital  invested  in 
that  country  will,  therefore,  be  exposed  to  a  risk  when  the  day  for  the 


46  PETROLEUM  IN  THE   ARGENTINE   REPUBLIC 

interpretation  of  the  present  laws  is  at  hand.  Assurances  that  are  now 
generously  given  will  avail  little  in  the  interpretation  of  the  law  when 
there  are  invested  possibly  several  millions  and  the  coveted  fluid  is 
gushing  from  the  wells. 

The  Argentine  Government's  venture  at  Comodoro  Rivadavia  would 
appear  to  be  profitable.  The  price  of  Comodoro  crude  at  Buenos  Aires 
last  November  was  100  pesos  per  metric  ton,  approximately  $6.50  per 
bbl.  It  is  improbable  that  the  rate  has  changed,  for  the  Government  has 
practically  a  monopolistic  control  over  the  production  to  date.  As  the 
production  of  the  field  is  about  5000  bbl.  per  day,  with  the  actual  delivery 
of  that  amount  to  the  market,  it  is  quite  obvious  that  there  would  be 
"something  wrong"  if  there  is  no  profit.  As  a  matter  of  fact,  the  books 
do  show  a  handsome  gain  over  expenditures.  The  property  is  not 
handled  in  a  most  efficient  manner,  nor  do  the  men  in  charge  think  it  is, 
for  they  admit  the  difficulties  of  Government  control. 


PETROLEUM   IN   THE   PHILIPPINES  47 


Petroleum  in  the  Philippines 

BY  WARREN  DuPR^  SMITH,*  PH.  D.,  EUGENE,  ORE. 


(New  York  Meeting  ,  February  ,  1920) 

IT  HAS  been  5  years  since  the  writer  left  the  Philippine  Islands  and 
while  in  that  country  his  chief  work  did  not  lie  in  this  field,  though  he  has 
visited  all  but  one  of  the  localities  mentioned  in  this  article.  The  princi- 
pal field  studies  relating  to  oil  were  made  by  his  colleague,  Mr.  Wallace 
E.  Pratt.  The  writer's  investigations  dealt  with  the  general  stratigraphy 
and  paleontology  of  the  Philippines.  With  the  exception  of  the  investi- 
gations made  by  Mr.  Pratt  and  the  writer  very  little  information  on  this 
subject  is  available. 

A  number  of  geologists  in  the  employ  of  large  oil  companies  have 
visited  the  Islands  from  time  to  time  but,  following  the  general  rule,  the 
public  has  scarcely  ever  been  permitted  to  learn  anything  of  the  results. 
The  writer  is  indebted  to  the  Bureau  of  Insular  Affairs,  Washington,  for 
late  information  regarding  recent  legislation  in  the  Islands  relating  to 
petroleum. 

All  the  known  oil  seeps,  petroleum  residues,  such  as  ozocerite,  and 
natural-gas  emanations  are  associated  with  Tertiary  sediments.  The 
chief  seeps  and  most  promising  prospects  are  located  as  follows  : 

1.  Bondoc  Peninsula  (lower  end),  Tayabas  Province,  Southeast  Luzon. 

2.  The  west  coast  of  the  island  of  Cebu  from  Alegria  north  to,  and 
perhaps  beyond,  Toledo. 

3.  Central  Mindanao  not  far  from  Lake  Lanao. 

4.  The  ozocerite  veins  on  the  Island  of  Leyte  in  the  northwestern 
part  in  the  vicinity  of  the  town  of  Villaba. 

5.  Natural  gas  from  some  deep  wells  in  Tertiary  shale  formations  on 
the  eastern  flank  of  the  Cordillera  and  extending  out  under  the  plain  on 
the  island  of  Panay. 

The  first  mention  in  geological  literature,  to  the  writer's  knowledge, 
of  gas  or  petroleum  in  the  Philippines  is  found  in  the  description  of  the 
Island  of  Panay  by  the  Spanish  geologist,  Abella,  in  the  year  1890.  In 
1898,  an  oil  well  was  being  dug  on  the  estate  of  Smith  Bell  &  Co.,  an  Eng- 
lish concern,  near  the  town  of  Toledo  on  the  west  coast  of  Cebu.  In 


*  Formerly  Chief,  Division  of  Mines,  Bureau  of  Science,  Manila. 


48 


PETROLEUM   IN    THE    PHILIPPINES 


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this  year,  an  insurrection  broke  out 
against  Spanish  rule  and  the  drillers 
were  driven  from  the  well,  which  was 
abandoned.  It  is  now  practically  as  the 
insurrectos  left  it;  that  is,  choked  with 
rubbish  which  would  have  to  be  cleared 
before  operations  could  be  renewed. 

About  1910,  a  number  of  Americans 
became  interested  in  the  petroleum  de- 
posits known  to  occur  on  the  peninsula 
of  Tayabas  in  the  southeastern  part  of 
Luzon,  and  which  were  apparently  un- 
known to  the  Spaniards.  Two  wells 
117  and  300  ft.  (35  and  91  m.)  respect- 
ively, were  dug  from  which  a  few  gallons 
of  oil  were  pumped,  but  nothing  has  been 
done  since  then,  as  far  as  we  know. 
At  the  end  of  1917,  there  was  consider- 
able excitement  in  the  Islands  over  the 
alleged  discoveries  of  oil  in  the  Lanao 
region  of  the  Island  of  Mindanao.  The 
existence  of  petroleum  on  that  island 
was  known  to  the  writer  as  early  as 
1908,  but  he  could  not  visit  the  localities 
owing  to  the  hostility  of  the  natives. 

In  1919,  an  Act  was  passed  by  both 
branches  of  the  Philippine  Legislature, 
and  approved  by  the  Governor-General 
on  Mar.  4,  providing  for  the  creation  of 
the  National  Petroleum  Co.  This  Act 
is  as  follows : 

Section  1. — A  company  is  hereby  or- 
ganized, which  shall  be  known  as  the  National 
Petroleum  Company,  the  principal  office  of 
which  shall  be  in  the  city  of  Manila,  and  which 
shall  exist  for  a  period  of  fifty  years,  from  and 
after  the  date  of  the  approval  of  this  Act. 

Section  2. — The  said  corporation  shall  be 
subject  to  the  provisions  of  the  Corporation 
Law  in  so  far  as  they  are  not  inconsistent  with 
the  provisions  of  this  Act,  and  shall  have  the 
general  powers  mentioned  in  said  Law  and  such 
other  powers  as  may  be  necessary  to  enable  it 
to  drill  wells  for  the  development  of  petroleum 
deposits,  and  to  work  said  deposits  and  sell  the 
output  thereof. 


50  PETROLEUM   IN   THE   PHILIPPINES 

Section  3. — The  capital  of  said  corporation  shall  be  five  hundred  thousand  pesos, 
divided  into  five  thousand  shares  of  stock  having  a  par  value  of  one  hundred  pesos 
each,  and  no  stock  shall  be  issued  at  less  than  par  nor  except  for  cash. 

Section  4. — The  Governor-General,  on  behalf  of  the  Government  of  the  Philip- 
pine Islands,  shall  subscribe  for  not  less  than  fifty-one  per  cent,  of  said  capital  stock, 
and  the  remainder  may  be  offered  to  the  provincial  and  municipal  governments  or  to 
the  public  at  a  price  not  below  par  which  the  board  of  directors  shall  from  time  to 
time  determine.  Ten  per  centum  of  the  value  of  all  stock  subscribed  shall  be  paid 
at  the  time-  of  the  subscription,  and  the  balance  thereof  shall  be  paid  at  such  time  as 
shall  be  prescribed  by  the  board  of  directors.  The  voting  power  of  all  such  stock 
owned  by  the  Government  of  the  Philippine  Islands  shall  be  vested  exclusively  in  a 
committee  consisting  of  the  Governor-General  and  the  presiding  officers  of  both  Houses 
of  the  Legislature. 

Table  1  gives  the  provisional  stratigraphic  column  of  the  Philippines. 
Table  2  furnishes  a  tentative  correlation  of  the  Far  Eastern  Tertiary 
stratigraphy  including  that  of  the  Philippines.  Some  of  the  shales  re- 
ferred here  to  the  Miocene  may  belong  to  the  Oligocene.  The  oil 
horizon  (there  may  be  more  than  one)  is  probably  in  the  Oligocene  or 
the  lower  Miocene  shales. 

Attention  is  called  to  an  error  in  the  stratigraphic  column  given  by 
the  writer  in  one  table  in  an  earlier  paper  and  incorporated  by  Pratt  in 
one  of  his.1  In  that  table,  the  Oligocene  is  given  as  resting  directly  upon 
a  pre-Tertiary  complex.  The  Eocene  is  well  developed  in  the  Philippine 
coal  fields  and  is  doubtless  to  be  found  in  the  oil  fields  as  well  as  in  the 
coal  fields,  though  perhaps  not  so  extensively. 

In  view  of  a  prevailing  opinion  that  these  islands  are  largely  volcanic, 
it  should  be  pointed  out  that  there  are  large  areas  where  the  only  surface 
rocks  are  sediments  and  other  areas  where  volcanic  rocks  form  a  veneer 
over  the  underlying  Tertiary  sandstones,  shales,  and  limestones.  In- 
trusive diorite  is  found  near  the  center  of  many  of  the  large  land  masses 
and  more  rarely  intrusive  granite,  andesitic  and  diabasic  intrusive  are 
also  found  in  many  places  near  the  borders  of  the  masses. 

The  section  made  by  the  streams  flowing  eastward  from  the  cordillera 
of  the  island  of  Panay  affords,  perhaps,  as  clear  a  view  of  the  sequence 
of  strata  comprising  a  part  of  the  Tertiary  as  can  be  obtained  anywhere 
in  the  Philippines.  The  dominant  formation  is  shale  with  thin-bedded, 
intercalated  sandstones  of  which  there  are  some  15,000  ft.  (4572  m.) 
along  the  Tigum  river.  These  shales  belong  to  the  same  horizon  as  those 
in  the  Bondoc  Peninsula,  known  as  the  Vigo  series,  and  are  Lower  Miocene 
or  Oligocene.  This  shale  yields  small  amounts  of  natural  gas,  which 
may  or  may  not  have  any  relation  to  small  coal  seams. 

Apparently  there  are  three  principal  shale  horizons;  lowermost,  the 
Eocene,  which  is  associated  with  sandstones  and  coal  seams;  next,  the 
Oligocene  or  Lower  Miocene,  in  which  the  oil  seeps  are  found;  and  upper- 
most, the  Miocene  with  more  coal  seams. 

1  Occurrence  of  Petroleum  in  the  Philippines.     Econ.  Geol.  (1918)  11,  247. 


WARREN  DUPRlD   SMITH 


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52  PETROLEUM   IN   THE   PHILIPPINES 

The  typical  oil  (Vigo)  shale  on  Bondoc  Peninsula  may  be  described 
as  (quoting  from  report  of  Pratt  and  Smith,  p.  331)  "consisting  of  fine- 
grained shale  and  sandy  shale  interstratified  in  thin  regular  beds  from 
5  to  10  cm.  in  thickness.  Occasional  beds  of  sandstone  occur  varying 
from  10  cm.  to  1  m.  in  thickness.  The  fine-grained  shale  is  gray,  blue,  or 
black  and  is  made  up  almost  entirely  of  clay.  The  blue  or  black  fine- 
grained shale  in  the  Vigo  formation  usually  emits  a  slight  odor  of  light 
oils  upon  fresh  fracture  and  in  some  outcrops  is  highly  petroliferous. 
The  material  loses  this  odor  and  assumes  a  light-gray  color  after  it  has 
been  exposed  to  the  air  and  becomes  thoroughly  dry."  These  shales 
contain  numerous  f oraminifera  of  the  genus  Globigerina,  which  may  be 
the  source  of  the  oil.  Although  present  numerously,  these  organisms 
did  not  appear  to  comprise  any  large  percentage  of  the  volume  of  these 
shales. 

On  the  island  of  Cebu  there  is  a  similar  shale  series,  dark  blue  in  color 
and  fine-grained,  in  which  the  oil  seeps  are  found. 

Another  important  feature  of  the  Philippine  Tertiary  is  the  presence 
of  several  limestone  horizons  in  striking  contrast  to  the  American  west 
coast  Tertiary.  These  limestones,  in  places,  attain  thicknesses  of 
several  hundred  feet. 

In  general,  we  may  say  that  the  Philippine  Islands  consist  of  a  series 
of  anticlinal  regions,  which  are  marked  by  the  island  masses,  and  syn- 
clines,  which  are  occupied  by  the  narrow  straits  between  the  islands. 
The  principal  folding  has  been  east  and  west,  with  minor  flexures  north 
and  south.  The  anticlines  are  generally  sharp,  as  is  the  case  in  Sumatra, 
Java,  Burma,  and  other  parts  of  the  Far  East.  In  South  Sumatra,  Tob- 
ler  has  shown  that  the  anticlines  are  only  2000  ft.  across  the  crest  and  that 
wells  must  be  located  on  the  crest  in  every  case.  In  Tayabas,  the  struc- 
ture can  easily  be  understood  by  a  study  of  the  map  accompanying  the 
paper  by  Pratt  and  the  writer.  This  shows  that  the  anticlines  are 
generally  sharp  and  the  dips  are  quite  steep.  The  Maglihi  anticline 
on  Bondoc  Peninsula  is  a  typical  example  and  less  than  J^  mi.  wide.  The 
axis  of  the  principal  structures  coincides  with  the  general  direction  of  the 
principal  tectonic  lines  of  the  archipelago;  i.e.,  north  and  south  with 
minor  departures  from  this.  Accompanying  this  folding  there  has  been 
more  or  less  faulting.  Just  how  great  the  throws  are,  not  enough  de- 
tailed work  has  been  done  to  determine.  There  is  enough  evidence  to 
indicate  a  considerable  amount  of  faulting  throughout  the  archipelago. 

On  Cebu,  Pratt  has  shown  that  the  seeps  near  Alegria  are  located  at 
the  crest  of  a  very  sharp  anticline.  The  well  near  Toledo,  which  shows 
some  oil,  is  apparently  on  a  monocline  in  which  the  beds  dip  50°  to  60° 
to  the  northwest. 

In  Leyte,  the  petroleum  seeps  are  along  the  outcrops  of  steeply  dip- 
ping strata  (Vigo  shale  series). 


WARREN   DUPRE    SMITH 


53 


On  Panay,  the  shale 
beds  yielding  natural  gas 
are  generally  monoclinal, 
but  there  is  one  well-defined 
anticline,  known  as  the 
Maasin  anticline,  which 
might  be  a  favorable  lo- 
cation for  a  test  well. 

In  Tayabas  and  Cebu, 
there  is  a  sandstone  mem- 
ber, to  which  the  local 
name  "Canguinsa  sand- 
stone "  has  been  given, 
which  lies  unconformably 
upon  and  overlapping  the 
great  shale  series.  In 
some  cases,  as  in  Leyte, 
residual  bitumens  are 
found  in  this  formation. 

Very  probably,  trans- 
portation will  depend  on 
inter-island  boats  as  most 
of  the  750  mi.  of  railroad  in 
the  archipelago  does  not 
tap  the  petroleum  localities. 
In  the  transportation  of 
machinery  and  the  location 
of  docks,  great  care  will 
have  to  be  exercised 
because  of  typhoons. 

Labor  is  plentiful  but 
unskilled.  However,  the 
Filipinos  show  a  great 
aptitude  along  mechanical 
lines  and,  under  competent 
white  foremen,  make  very 
excellent  workmen.  The 
prices  for  labor  vary  with 
the  different  tribes  and 
localities.  Present  prices 
are  commensurate  with 
those  in  other  parts  of  the 
world.  The  Filipino's 
fondness  for  holidays  ne- 


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u 

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•£* 

O  .-i 


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o 
^ 

Ills 


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I    1 

*=        p. 


54  PETROLEUM  IN  THE   PHILIPPINES 

cessitates  a  larger  pay-roll  than  is  usually  warranted  by  the  size  of  the  job. 
The  manager  will  have  to  take  this  into  account. 

Philippine  petroleum  has  a  paraffine  base  and  is  usually  reddish  to 
violet  in  color.  It  is  quite  clear,  and  closely  resembles  oil  from  Burma 
and  Sumatra.  Table  3  gives  a  fairly  complete  analysis  made  by  Rich- 
mond, former  chemist  of  the  Bureau  of  Science,  and  others.  Table  4 
contains  an  analysis  of  the  petroleum  residue  from  the  Island  of  Leyte. 
The  paraffine  content  of  the  Philippine  petroleum  is  very  high;  a  beer 
bottle  full  of  oil  from  the  Toledo  well  in  1908,  which  the  writer  col- 
lected and  put  imperfectly  sealed  into  his  saddle  bags,  on  unpacking  three 
days  later,  contained  no  oil  but  was  half  full  of  solid  paraffine. 

The  residual  bitumens  from  Villaba,  Leyte,  are  found  in  lenses  and 
pockets  in  the  Canquinsa  sandstone.  These  have  been  fully  investi- 
gated by  Pratt.  Physically  they  more  nearly  correspond  to  ozocerite 
than  to  any  other  of  the  natural  bitumens. 

TABLE  4. — Physical  Properties  of  Natural  Bitumens  from  Villaba,  Leyte 

OUTCBOP  OUTCROP 

PROPERTY     A  AND  B  PROPERTY          A  AND  B 

Specific  gravity. . .   1 . 05  Luster Brilliant 

Hardness 2. 00  Structure Columnar 

Color Jet  black  Fracture Conchoidal 

Streak Black  Flows Intumesces,     softens, 

and  flows  imperfectly 
at  150°  C. 

The  writer  agrees  with  Pratt  in  the  belief  that  there  is  a  small  com- 
mercial supply  of  oil  in  the  Philippines,  very  much  as  in  Formosa.  He 
seriously  doubts,  however,  that  petroleum  exists  in  large  enough  quantities 
to  attract  large  capital  from  America,  considering  the  distance  and  the 
many  unfavorable  conditions  to  be  encountered.  The  size,  steepness 
of  dip,  and  broken  nature  of  many  of  the  structures  are  not  favorable 
to  large  production. 

All  the  oil  which  the  writer  has  seen  in  the  Islands  is  in  the  shallow  wells 
mentioned  and  in  seeps  in  shales,  and  these  seeps  have  been  small.  He 
has  seen  no  oil  in  beds  either  below  or  above  these  shales.  In  the  petro- 
liferous shales  are  a  number  of  forminifera  with  Globigerina  predomi- 
nating. It  may  be  that  all  the  oil  has  come  from  the  decomposition  of 
these  organisms. 

DISCUSSION 

WALLACE  E.  PBATT,*  Houston,  Tex.  (written  discussion).— Doctor 
Smith's  correction  of  my  statement  in  Economic  Geology  that  the  Philip- 
pine Oligocene  rests  directly  upon  a  pre-Tertiary  basement  of  crystalline 


*  Chief  Geologist,  Humble  Oil  &  Refining  Co. 


DISCUSSION  55 

rocks  is  well  taken.  I  concede  that  some  of  the  older  indurated  shales 
and  limestones  may  properly  be  classed  as  Eocene.  My  statement 
should  have  been  limited  to  the  petroleum-bearing  areas  that  I  described 
and  in  which  it  applies  by  reason  of  the  absence  of  the  older  rocks. 

In  this  connection,  I  may  record  my  impression  that  the  typical 
Philippine  section  is  not  as  thick  as  the  15,000-ft.  (4572  m.)  section  ex- 
posed on  the  eastern  flank  of  the  cordillera  of  the  Island  of  Panay  and 
mentioned  by  Doctor  Smith.  I  think  the  average  thickness  for  the 
Philippine  sedimentary  column  would  be  about  one-third  of  the  figure 
quoted.  The  Panay  section  is  unusual  in  another  respect;  at  its  base 
there  are  thousands  of  feet  of  unfossiliferous  conglomerates  and  coarse 
sands  which  appear  to  be  of  extreme  shallow-water  origin,  whereas  in  the 
typical  column  this  basal  member  is  not  more  than  200  ft.  (61  m.)  thick. 

A  recent  press  dispatch  states  that  Cebu,  the  second  largest  port  in 
the  Philippine  Islands,  and  a  city  of  about  100,000  population,  is  now 
paving  its  streets  with  rock  asphalt  secured  from  a  quarry  in  the  vicinity 
of  the  town  of  Villaba,  on  the  neighboring  island  of  Leyte.  I  believe  this 
work  marks  the  first  commercial  use  of  the  petroliferous  deposits  of  the 
Philippines.  The  circumstance  is  interesting  not  only  as  a  first  step 
in  making  this  natural  resource  serve  industry,  but  as  an  evidence  of  the 
extent  of  the  residual  deposits  that  constitute  the  surface  indications  of 
petroleum  in  one  of  the  possible  oil  fields  in  the  Philippines. 

As  a  matter  of  fact,  not  only  is  the  stratigraphic  column  in  the  Philip- 
pines — dominantly  shale  with  interbedded  sandstone  as  described  by 
Doctor  Smith — of  suitable  character  and  adequate  thickness  to  yield 
commercial  petroleum,  but  the  surface  evidences  of  the  existence  of 
petroleum  on  some  of  the  islands  are  quite  remarkable.  These  various 
seepages  and  asphalt  deposits  are  described  briefly  in  my  paper  in  Eco- 
nomic Geology  to  which  Doctor  Smith  refers.2 

The  situation  in  the  Philippines,  in  so  far  as  the  geologic  conditions 
are  concerned,  is  certainly  one  that  would  lead  many  of  the  geolo- 
gists engaged  in  the  present  fervid  search  for  new  petroleum  fields 
to  recommend  drilling  exploration  on  some  of  the  islands,  provided 
their  clients  commanded  adequate  capital.  The  possibilities  in  the 
Philippines  are  the  more  impressive  when  one  reflects  that  in  Borneo, 
Sumatra,  and  Java,  as  well  as  in  Formosa  and  Japan,  commercial  produc- 
tion of  a  petroleum  similar  in  character  to  that  which  comes  to  the  surface 
at  places  in  the  Philippines  is  obtained  from  beds  of  the  same  geologic 
age  and  composition  as  those  in  the  Philippines. 

2  More  detailed  descriptions  with  maps  and  geologic  sections  will  be  found  in 
the  following  references:  Wallace  E.  Pratt  and  Warren  D.  Smith:  Geology  and 
Petroleum  Resources  of  the  Southern  Part  of  Bondoc  Peninsula,  Tayabas  Province, 
Philippines.  Phil.  Jnl  Sci.,  Bur.  Sci.,  Manila  (1913)  Sec.  A,  5,  301-376;  Wallace  E. 
Pratt;  Occurrence  of  Petroleum  in  Cebu,  Id&m.  (1915)  Sec.  A,  4;  Wallace  E.  Pratt: 
Petroleum  and  Residual  Hydrocarbons  in  Leyte,  Idem.  (1915)  Sec.  A,  4, 


56  PETROLEUM   IN   THE    PHILIPPINES 

Under  different  conditions,  a  prospect  like  that  in  the  Philippines 
would  evoke  an  active  drilling  campaign.  I  have  had  opportunity  to 
make  direct  comparison  in  the  field  between  conditions  in  parts  of  Cen- 
tral America,  for  instance,  and  in  the  Philippines  and  I  can  conceive  no 
possible  contention  but  that  the  geologic  conditions  in  the  Philippines 
are  decidedly  the  more  promising.  Yet  these  same  regions  in  Central 
America  have  interested  dozens  of  large  petroleum  corporations;  con- 
cessions there  have  been  sought  eagerly  for  years  and  are  at  present, 
indeed,  being  exploited. 

I  am  convinced  that  adequate  exploration  of  the  petroleum  deposits 
in  the  Philippines  has  been  prevented,  not  by  unfavorable  geologic  con- 
ditions but  by  prohibitive  regulations  of  the  local  mining  laws.  Practi- 
cally all  the  possibly  petroleum-bearing  territory  in  the  Philippines  is 
government  land.  It  can  be  acquired  only  under  laws  similar  to  the 
mining  laws  of  the  United  States.  Petroleum  lands  are  subject  to 
"location"  as  placer-mining  claims.  An  individual  may  obtain  a  single 
claim  of  8  hectares  (20  acres)  in  any  one  field  while  a  corporation  compris- 
ing eight  individuals  can  secure  only  one  claim  of  64  hectares  (160  acres) 
in  any  one  field.  Except  by  a  direct  evasion  of  the  law,  therefore,  it  is 
impossible  to  control  the  acreage  requisite  for  large  operation,  such  as 
must  be  contemplated  by  any  enterprise  that  looks  as  far  afield  as  the 
Philippine  Islands. 

It  is  unlikely  that  successful  exploration  will  result  from  the  efforts  of 
the  Government  owned  corporation,  the  formation  of  which  is  recorded 
in  the  legislation  quoted  by  Doctor  Smith.  This  corporation,  like  any 
other,  is  subject  to  the  laws  that  prevent  the  acquisition  of  suitably  large 
holdings  and  its  capitalization  of  500,000  pesos  ($250,000)  is  not  adequate. 
If  the  Filipinos  were  to  grant  concessions  of  hundreds  of  thousands  of 
acres,  as  some  of  the  Central  and  South  American  republics  have  done, 
I  believe  their  possible  petroleum  resources  would  be  promptly  and  thor- 
oughly tested  by  the  drill. 

DAVID  WHITE,*  Washington,  D.  C. — This  paper  is  very  timely  since 
the  Philippine  Islands  are  presumably  open  to  the  enterprise  of  the  Amer- 
ican driller,  whereas  much  of  the  territory  in  that  part  of  the  world  is 
closed  to  us. 

The  United  States  has  ambitious  plans  for  the  operation  of  a  great 
merchant  marine,  which  is  to  be  oil  burning  in  the  main,  and  it  takes  but 
a  glance  at  the  world  map  to  see  the  strategic  advantage  of  oil  supplies  in 
the  Philippines  for  such  marine  operations.  It  is  a  little  difficult  to 
understand  why  more  attention  has  not  been  given  to  the  Philippines,  in 
spite  of  the  difficulties  attending  development  in  these  islands. 


*  Chief  Geologist,  U.  S.  Geol.  Survey. 


DISCUSSION  57 

A  number  of  American  oil  companies  are,  I  believe,  at  the  present 
moment  taking  an  interest  in  the  possibilities  of  the  Philippines.  Im- 
portant factors  in  the  formulation  of  opinion  regarding  the  importance 
of  the  oil  deposits  of  the  Philippines,  as  brought  out  by  Mr.  Pratt,  are 
the  point  of  view  and  the  breadth  of  experience  of  the  examining  geologist. 
The  average  oil  geologist,  whose  experience  has  been  mainly  in  the 
Appalachian  region,  the  Mid-Continent,  or  Louisiana,  or  possibly  even  in 
California,  on  seeing  the  narrowness  of  the  basins,  the  closeness  of  the 
folding,  and  the  presence  of  igneous  rocks  here  and  there,  would  be  likely 
to  draw  unfavorable  conclusions  as  to  the  possibilities  of  the  Philippine 
Islands.  Geologists  visiting  that  region  should  be  familiar  with  the 
geological  conditions  of  oil  occurrence  in  Japan,  Formosa,  the  East 
Indies,  or  in  the  Baku  district,  and  their  conclusions  should  be  formulated 
with  the  knowledge  and  understanding  of  the  occurrence  of  oil  in  those 
regions  rather  than  in  the  United  States. 


58  PETROLEUM  INDUSTRY  OF  TRINIDAD 


Petroleum  Industry  of  Trinidad 

BY  GEORGE  A.  MACREADY,  Los  ANGELES,  CALIF. 

(St.  Louis  Meeting,  September,  1920) 

TRINIDAD,  British  West  Indies,  is  an  island  near  the  north  coast  of 
South  America,  situated  between  latitudes  10°  and  11°  N.,  and  opposite 
the  numerous  outlets  of  the  Orinoco  River  Delta.  It  is  separated  from 
Venezuela  by  the  Gulf  of  Paria  (salt  water)  and  straits  over  5  mi.  (8 
km.)  wide.  The  area  of  the  island  is  approximately  1750  sq.  mi.  (453,- 
250  hectares)  and  the  population  is  approximately  400,000.  The  climate 
is  tropical  with  an  annual  rainfall  of  from  45  to  60  in.  (114  to  152  cm.). 
The  oil  fields  consist  of  several  units,  or  fields,  located  in  the  southern 
half  of  the  island.  Approximately  90  per  cent,  of  the  total  production 
has  been  yielded  by  fields  situated  within  7  mi.  (11.3  km.)  of  the  famous 
asphalt  lake  and  on  the  southwest  peninsula. 

The  most  important  producing  fields,  or  units,  are  the  following, 
which  are  shown  on  the  accompanying  map: 

Brighton,  or  Pitch  Lake  Field,  operated  by  the  Trinidad  Lake  Pe- 
troleum Co.,  Ltd.,  is  situated  beside  the  famous  Pitch  Lake;  it  even  en- 
croaches on  the  lake. 

Vessigny  Field,  operated  by  the  Trinidad  Lake  Petroleum  Co.,  Ltd., 
is  situated  2  mi.  (3.2  km.)  south  of  Pitch  Lake. 

Lot  One  Field,  operated  by  the  Petroleum  Development  Co.,  Ltd., 
the  United  British  Oilfields  of  Trinidad,  Ltd.,  and  Stollmeyer,  Ltd., 
is  situated  3  mi.  south  of  Pitch  Lake  upon  Lot  One  of  Morne  PEnfer 
Forest  Reserve  and  adjoining  properties. 

Parry  Lands  Field,  operated  by  the  United  British  Oilfields  of  Trini- 
dad, Ltd.,  and  the  Petroleum  Development  Co.,  Ltd.,  is  situated  3J^ 
mi.  south  of  Pitch  Lake  on  Lot  Three  of  Morne  1'Enfer  Forest  Reserve 
and  adjoining  properties. 

Point  Fortin  Field,  operated  by  the  United  British  Oilfields  of  Trini- 
dad, Ltd.,  is  situated  at  Point  Fortin,  6  mi.  southwest  of  Pitch  Lake. 

Fyzabad  Field,  operated  by  Trinidad  Leaseholds,  Ltd.,  is  situated 
several  miles  southwest  of  Fyzabad  Village  and  6  mi.  south-southeast  of 
Pitch  Lake. 

Barracpore  Field,  operated  by  Trinidad  Leaseholds,  Ltd.,  is  situated 
several  miles  south  of  San  Fernando  and  15  mi.  (24.14  km.)  east  of  Pitch 
Lake. 


GEORGE   A.   MACREADY 


59 


Tabaquite  Field,  operated  by  Trinidad  Central  Oilfields,  Ltd.,  is 
situated  4  mi.  southeast  of  Tabaquite  Railroad  Station,  and  30  mi. 
(48.28  km.)  northeast  of  Pitch  Lake. 


If 


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111 


Guayaguayare  Field,  operated  by  Trinidad  Leaseholds,  Ltd.,  is  situ- 
ated in  the  extreme  southeast  corner  of  the  island  45  mi.  (72.42  km.) 
from  Pitch  Lake. 

From  1870  to  1900,  several  attempts  were  made  to  obtain  oil  on  Trini- 


60  PETROLEUM   INDUSTRY   OF  TRINIDAD 

dad  but  although  small  quantities  of  oil  were  encountered,  no  com- 
mercial production  resulted,  and  most  of  the  wells  were  abandoned. 
An  attempt  was  also  made  to  obtain  oil  from  the  crude  lake  asphalt, 
probably  by  a  cracking  process,  but  without  commercial  success. 

The  present  industry  can  be  said  to  commence  with  wells  drilled  since 
1900  near  Guayaguayare,  in  the  extreme  southeast  corner  of  the  Island. 
Several  years  later  wells  were  drilled  near  Point  Fortin,  southwest  of 
Pitch  Lake,  which  yielded  commercial  quantities  of  oil  but  not  sufficient 
for  export. 

In  1908,  the  New  Trinidad  Lake  Asphalt  Co.,  Ltd.,  commenced  drill- 
ing at  the  Pitch  Lake  and  encountered  an  excellent  flow  of  oil  in  its  second 
well.  Other  wells  were  drilled  and,  in  1910,  this  company  exported  the 
first  steamship  cargo  of  oil  from  Trinidad.  Since  then,  the  quantity  of 
oil  produced  and  the  number  of  companies  exporting  has  increased.  The 
production  in  1908  was  169  bbl.,  in  1912,  436,805  bbl.;  and  in  1917, 
1,599,455  bbl. 

GEOLOGY 
Stratigraphy 

All  petroleum  produced  by  Trinidad  has  been  yielded  by  strata  of 
Tertiary  age.  In  general,  the  Tertiary  strata  consist  of  clays,  shales, 
marls,  and  sandstones;  conglomerate  is  extremely  rare  and  limestone  is 
uncommon.  The  sandstone  is  usually  composed  of  small  quartz  grains 
uniformly  sorted.  Cretaceous  and  metamorphic  rocks  underlie  the 
Tertiary.  The  most  important  portion  of  the  Tertiary  strata  consists 
of  sandstone  and  shale,  which  grades  upward  into  marl  and  shale  con- 
taining marine  organic  material  and  evidences  of  petroleum.  The  organic 
material  in  this  shale  is  probably  the  primary,  or  "mother,"  source 
from  which  Trinidad  petroleum  is  derived.  The  upper  portion  of  the 
shale  contains  sandy  strata  into  which  petroleum  has  migrated  and  ac- 
cumulated in  quantities  sufficient  for  commercial  exploitation.  Eocene 
fossils  occur  in  the  lower  part,  but  the  upper  part  may  extend  into  the 
Oligocene.  This  includes  the  Naparima  clay,  Cruse  oil  zone,  and  Stoll- 
meyer  oil  zone. 

The  Morne  PEnfer  formation  unconformably  overlies  the  above- 
mentioned,  and  consists  of  sandstone  and  clay  shale  in  approximately 
equal  proportions.  The  lower  sandstones  are  often  heavily  impregnated 
with  asphalt  and  often  outcrop  as  " pitch  sand"  cliffs.  The  author 
believes  that  this  asphalt  has  migrated  from  the  underlying  shales  and 
marls.  Near  Pitch  Lake,  some  oil  may  be  produced  from  this  formation. 
Strata  younger  than  the  Morne  TEnfer  have  not  yielded  commercial 
quantities  of  oil  and  are  unimportant. 

The  accompanying  tabulation  describes  the  geological  formations  of 


GEORGE   A.    MACREADY  61 

Trinidad  in  more  detail.      The  areal  distribution  of  the  formations  is 
shown  approximately  on  the  map. 

Structure 

The  areal  geology  of  the  island  is  separated  into  two  parts  by  the 
great  east- west  fault  passing  near  Port  of  Spain  and  Matura,  and  ex- 
tending from  the  Atlantic  Ocean  into  Venezuela.  North  of  the  fault  is 
the  area  of  Metamorphics,  forming  the  Northern  Mountain  Range. 
South  of  the  fault  is  a  great  undulating  blanket  of  Tertiary  strata. 

The  dominating  features  of  the  Tertiary  structure  are:  A  synclinal 
or  monoclinal  trough  between  the  Central  and  Northern  Mountain 
Ranges;  an  anticlinal  uplift  along  the  south  side  of  the  Central  Range 
striking  east-northeast  by  west-southwest,  from  Pointe  a  Pierre  to  Nariva 
Swamp ;  an  undulating  synclinal  structure  between  San  Fernando,  May- 
oro  Point,  Guayaguayare  Bay,  and  Icacos  Point  with  an  east-west  strike; 
the  magnitude  of  erosion  at  the  unconformity  below  the  Morne  1'Enfer 
formation.  Numerous  local  folds,  faults,  kinks,  anticlines,  and  synclines 
modify  the  broader  features  and  are  very  important  in  the  concentration 
of  petroleum. 

Occurrence  oj  Petroleum 

All  the  producing  oil  fields  of  Trinidad  (except  Tabaquite  Field)  are 
within  or  on  the  flanks  of  the  great  synclinal  trough  or  basin  of  the 
southern  part  of  Trinidad.  Most  of  them  are  on  the  southwest  penin- 
sula. This  undulating  synclinal  structure  is  underlain  by  Naparima 
clays,  marls,  and  organic  shales.  It  forms  the  drainage  area  from  which 
petroleum  has  accumulated.  This  petroleum  has  concentrated  in  com- 
mercial quantities  near  anticlinal  folds. 

The  location  and  richness  of  each  productive  area  are  modified  by 
the  magnitude  and  condition  of  the  unconformity  below  the  Morne 
TEnfer  formation:  by  the  channels  of  migration:  by  the  local  conditions 
of  porosity  of  reservoir  sands;  by  the  lenticular  condition  of  the  oil 
sands;  by  the  facility  with  which  connate  salt  waters  were  displaced  by 
oil.  There  are  three  principal  horizons  in  which  petroleum  usually, 
but  not  always,  is  concentrated  in  commercial  quantities. 

The  Cruse  oil  zone  is  persistent  because  its  proximity  to  the  organic 
shales  permits  ready  saturation,  has  permitted  much  time  for  connate 
waters  to  be  forced  out,  and  Tertiary  erosion  has  not  attacked  it  as 
frequently  as  higher  strata.  Its  thinness  and  high  gas  pressure  increase 
operating  cost.  This  condition  applies  at  Parry  Lands,  Morne  1'Enfer 
Forest  Reserve,  and  Point  Fortin. 

The  Stollmeyer  oil  zone  overlies  the  organic  shales  and  the  sands  are 
lenticular.  The  porosity  and  saturation  of  the  oil  sand  varies  locally. 


62  PETROLEUM   INDUSTRY   OF  TRINIDAD 

It  may  or  may  not,  locally,  be  conformable  below  the  Morne  PEnfer 
formation  or  it  may  be  entirely  missing.  Where  apparently  conformable 
below  the  Morne  PEnfer  formation,  conditions  are  simple  and  anticlinal 
structures  may  prove  very  rich,  as  in  the  Morne  PEnfer  Forest  Reserve. 
As  the  unconformity  increases,  modifications  occur.  Part  of  the  Stoll- 
meyer  sand  may  have  been  removed  by  erosion  and  the  remainder  sealed 
by  the  clayey  base  of  the  Morne  PEnfer  formation.  One  flank  of  an 
anticline  may  prove  richer  due  to  better  drainage  area  on  that  side,  as 
may  be  the  case  at  Lot  One.  A  flank  of  the  anticline  may  be  enriched  but 
the  apex  barren  because  the  sand  is  missing;  such  may  be  the  case  at 
Point  Fortin,  Barracpore,  and  possibly  at  Brighton.  Connate  salt  water 
has  not  been  completely  forced  out  of  all  the  sand  lenses  but  usually 
remains  only  in  the  lowest  lenses. 

The  Morne  PEnfer  formation  is  enriched  by  oil  migrating  from  the 
underlying  organic  shales.  Where  the  organic  shales  lie  close  below  as  a 
result  of  Tertiary  erosion  and  the  Morne  PEnfer  sands  are  not  too  thick 
or  too  clayey  at  the  base,  saturation  may  be  sufficient  for  commercial 
production;  such  may  be  the  condition  in  fields  near  Pitch  Lake.  Where 
the  sand  is  too  thick  and  petroleum  has  migrated  slowly,  saturation  may 
not  be  sufficient  for  commercial  production;  such  may  be  the  condition 
of  pitch  sands  in  the  Forest  Reserve. 

Near  Tabaquite,  petroleum  has  concentrated  in  sands  closely  associ- 
ated with  organic  shales  but  too  distant  from  other  fields  for  correlation. 

TECHNOLOGY 
Drilling 

The  rotary  system  of  drilling  has  proved  most  successful  in  the  produc- 
tive fields.  Cable  tools  are  usually  confined  to  some,  but  not  all,  isolated 
test  wells,  to  special  work,  and  to  repairing  damaged  wells;  but  in  the 
early  days  many  wells  were  drilled  and  finished  with  them.  Portable 
drilling  machines  have  been  successful  for  shallow  wells  in  the  central 
and  extreme  southern  portions  of  Trinidad.  Some  wells  have  been 
drilled  with  Canadian  and  Galacian  outfits. 

Some  difficulty  is  encountered  in  penetrating  pitch  strata.  If  sandy, 
they  are  hard  and  wear  off  rotary  bits.  If  clayey,  they  are  plastic  and 
squeeze  slowly  but  persistently  into  the  hole  and  grip  the  drill  pipe  above 
the  bit;  this  has  been  overcome  by  using  hot  water  circulation  and  driving 
casing  through  the  pitch. 

For  wells  expected  to  be  over  1000  ft.  (305  m.)  deep,  it  is  common 
practice  to  drill  with  rotary  and  set  15^  in-  70-lb.,  13-in.  54-lb.,  or  12^- 
in.  50-lb.  screw  casing  as  the  outside  string.  Either  this  or  the  succeeding 
one  is  used  to  shut  off  water  preferably,  but  not  always,  by  cementing. 
Wells  are  usually  drilled  into  the  oil  sand  using  6-in.  (15.24-cm.)  or  8-in. 


GEORGE   A.   MACREADY  63 

perforated  drill  pipe  equipped  with  a  blow-out  preventer  on  an  outer 
string.  With  all  in  readiness  to  receive  a  big  flow  of  oil,  drilling  proceeds 
until  the  oil  sand  is  drilled  through  or  the  flow  of  oil  and  gas  prevents  far- 
ther progress.  Then  the  drill  pipe  is  left  as  it  is  and  the  wash  pipe 
recovered  when  convenient.  In  shallow  fields,  a  common  practice  is  to 
set  about  100  ft.  (30.5  m.)  of  12^-in.  (31.75-cm.)  casing  as  a  conductor 
and  then  to  drill  through  the  oil  zone.  Perforated  casing  is  substituted 
for  drill  pipe  and  the  well  tubed  to  pump  or  flow  as  the  case  may  be. 

Casing  is  not  perforated  in  the  well  if  it  can  be  avoided;  the  usual 
practice  is  to  set  shop  perforated  casing.  Screen  casing  has  not  been 
successful  because  of  clogging  with  clay.  Explosives  are  never  used  to 
increase  production  and  rarely  to  break  up  junk. 

For  a  well  1500  ft.  (457.2  m.)  deep,  60  days  is  a  fair  average  time  from 
first  actual  drilling  until  production  begins.  This  includes  usual  delays, 
casing  setting,  changing  crews,  waiting,  etc.  The  actual  number  of 
days  in  which  hole  is  dug  may  be  as  low  as  fourteen.  In  1918,  $15,000 
was  a  fair  average  cost  to  the  depth  of  1500  feet. 

Production 

Wells  in  the  thin  deep  sands  usually  begin  production  with  a  large 
initial  flow  or  gust  under  great  gas  pressure,  yielding  up  to  100,000  bbl. 
in  the  first  few  days  and  later  choking  with  sand  or  shale.  During  the 
first  year,  the  production  is  dependent  largely  on  spasmodic  flows  aided 
by  bailing  or  tubing  agitation,  but  after  the  first  year  few  wells  yield 
over  100  bbl.  daily.  The  shallower  wells  with  thicker  oil  sands  begin 
production  sometimes  as  pumpers  and  sometimes  by  flowing.  The 
initial  flow  averages  much  less  than  for  the  deeper  wells,  but  is  less 
spasmodic  and  less  costly  to  control.  Few  wells  flow  for  over  a  year. 

After  wells  cease  flowing  they  are  usually  pumped  by  the  walking 
beam.  Sand  and  mud  must  be  cleaned  out  frequently  for  two  years  or 
more.  None  of  the  southwest  fields  have  been  successful  in 
pumping  from  a  central  power  or  jack.  Few  wells  have  produced  over 
eight  years  and  many  cease  producing  in  the  second  or  third  year.  The 
production  of  individual  wells  is  greatly  influenced  by  the  local  porosity 
of  the  oil  sand  and  the  size  of  individual  oil-sand  lenses. 

Character  oj  Petroleum 

Trinidad  petroleum  varies  greatly  in  specific  gravity,  not  only  in 
different  fields,  but  also  within  the  same  field.  It  is  (with  one  exception) 
of  asphaltic  base.  Oil  from  the  Trinidad  Central  Oil  Fields,  Ltd.,  near 
Tabaquite  has  little  asphalt  but  some  paraffine,  and  yields  much  gaso- 
line and  kerosene  by  distillation.  The  average  specific  gravities  for 


64 


PETROLEUM   INDUSTRY   OF   TRINIDAD 

Geologic  Column  of  Trinidad 


Name 

Thick- 

Lithology 

Age 

of 
p__ 

ness. 

Petroleum  Evidence 

Miscellaneous  Remarks 

r  or* 
mation 

Feet 

Folding 

40 

Principally  soft  clay,  silt,   vegetable 

Consists     of    stream     alluvium     and 

«• 

p 

remains      Less   sand.     Rarely   con- 

swamp  deposits. 

8 

*S 

gloineritic. 

I 

I 

Asphalt  cnnes  and  seepages  and  mud 

H 

3 

volcanoes  occur  by  breaking  through 

•< 

from  underlying  formations. 

Never  tilted. 

i 

Unconformity 

100 

Ferruginous    sands,    clays    and    con- 

The Llanos  formation  consists  of  ma- 

glomerates. 

terial  deposited  in  the  basin  of  which 

Evidences  of  asphalt  occur  by  break- 

the   present    Orinoco    Valley    was   a 

ing    through    from    underlying    for- 

portion     Large  areas  occur  in  Vene- 

mations 
Usually  nearly  flat;  rarely  tilted  to  5° 

zuela,  particularly  in  the  Llanos,  or 
plains,  of  the  Orinoco  River  Valley, 
but  in  Trinidad  where  the  formation 

g 

appears  thinner,  erosion  has  dissected 

£• 

O 

•.3 

it  until  only  hill-top  remnants  and  a 

*-* 

l 

few  larger  areas  remain. 

2 

s 

When  seen  from  the  Gulf  of  Paria,  the 

« 

0 

topography  of  southern  Trinidad  has 

o 

fc 

the    appearance    of    a    former    flat 

is' 

o 

surface,  such  as  a  sea  bottom,  up- 

•2 

ft 

lifted   to   a   plateau    100   to   300  ft. 

P^i 

g 

above     sea     level     through      which 

H 

"islands"  or  peaks  of  older  resistant 

rocks    project.      (Erin    Peak,    Morne 
1'Enfer.    Soldado    Rock,     Naparima 

Hill     for     example.)     The     present 

drainage  system   has   dissected   this 

plateau  into  a  low,  but  steep  topo- 

graphy   gentler   than    canyon   topo- 

graphy. 

1 

Unconformity 

i 

400 

Porcellanite,     lignitic     clay,     lignite,  i  Usually  occurs  within  synclines  flanked 
partly  altered  wood,  shale,  clay,  and      by   the  1'Enfer  formation.     It  may 
sandstone^  exhibiting    great    lateral      be  of  fresh-water  origin  of  material 

£• 

& 

variation  in  character.     Conglomer-  j    derived     from     the     older     tertiary 

II 

atee  not  known.                                          rocks.     In  troughs,  or  synclines,  de- 
Rarely  contains  asphalt  and  has  no      position  may  have  been  uninterrupted 
commercial  oil  horizons.                            between  this  and  the  Llanos  forma- 

§ 

H§ 

Usually  found  tilted  but  rarely  over 

tion. 

a 

35°. 

This    formation    corresponds    to    the 

P-I 

Q. 

upper  tertiary  strata  in  reports  of 

s 

E.  H.  Cunningham-Craig. 

D 

Porcellanite  has  not  been  proved  to 

exist  in  other  formation  in  Trinidad. 

Unconformity  (locally) 

2500 

Sandstones  of  uniform  small  quartz 

The  following  thicknesses  have  been 

^ 

fl 

grains  separated  by  bands  of  clay 

measured:     2500    ft.    at    Erin    Bay, 

d 

.s 

shale  and  rarely  by  lignite. 

1200  ft.  at  Guapo  Bay,  900  ft.  at 

g 

4 

No  conglomerate  known.                            Vessigny    Bay,    800    ft.    at    Morne 

<3 

s 

The    lowest    sands    are    commonly 

1'Enfer. 

m 

o 

saturated  with  asphalt.    Near  Morne 

Fossils  of  doubtful  Oligocene  age  have 

o5 

w 

1'Enfer  300  ft.   of  "tar  sand"  has 

been  found  near  this  formation.     In 

is 

Px> 

I 

*2 

been  observed  in  the  lowest  700  ft., 
some  of  which  was  very  rich. 

the  Central  Range  mountains,  Mio- 
cene fossils  occur  in  what  may  be  the 

l?o 

H 

Some  of  the  oil  fields  nearest  the  Pitch 

equivalent    formation      Because    of 

s* 

Lake   may  derive   production   from 

the   great   unconformity   below    this 

1 

§ 

sands  of  this  formation. 

formation,    the    author    prefers    to 

a 

S 

Tilting   is    commonly    over   20°   but 
rarely  as  much  as  90°. 

regard  it  as  Miocene. 
The  name  of  this  formation  is  selected 

O 

0H 

because    of    its    occurrence    in    the 

I 

Morne  1'Enfer  Forest  Reserve. 

>>          600 

Blue  and  gray  clay  often  very  sticky. 

This  forms  the  impervious  cover  over 

o§ 

So 

i 

the  Stollmeyer  oil  zone. 
The  author  is  convinced  that  there  is  a 

O                    43 

great  unconformity  below  the  Morne 

O-j?              ^ 

1'Enfer  formation,  but  owing  to  the 

wo      £ 

clayey   non-resistant   nature   of   the 

VOL.  LXV.— 5 


GEORGE   A.   MACBEADY 


65 


Age 

Name 
of 
For- 
mation 

Thick- 
ness 
Feet 

Lithology 
Petroleum  Evidence 
Folding 

Miscellaneous  Remarks 

Eocene  or  Oligocene 

§ 

| 

strata  the  exact  horizon  is  difficult 
to  identify.     It  probably  occurs  in 
these  clays,  below  the  lowest  Morne 
1'Enfer  sand. 
This  condition  was  observed  by  the 
author  on  a  much  smaller  scale  at  a 
small   island    which    rose    overnight 
from  the  sea  near  Trinidad  in  1911. 
A  few  weeks  later  waves  had  eroded 
it    completely    and    deposited    tne 
material  on  similar  adjacent  clayey 
material. 

Unconformity 

1  Eocene  or  Oligo" 
cene 

Stollmeyer  Oil 
Zone 

500 

Overlapping  pancake-shaped  lenses  of 
sand  and  shale  alternating. 
The  sands  contain  oil  and  salt  water, 
the  best  saturation  of  oil  being  in  the 
upper  part  of  tne  zone  and  not  far 
from  an  anticlinal  axis. 
Salt  water  is  usually  confined  to  the 
lower  lenses,  but  has  been  found  at 
the  top  of  the  zone. 

This  is  the  most  profitable  oil  forma- 
tion on  Trinidad. 
It  is  difficult  to  correlate  individual 
lenses  from  well  ±o  well  but  the  group 
or  zone  can  easily  be  traced  through  a 
field. 

Eocene  or 
Oligocene 

I! 

3Z 

COQ 

600 

Principally  clay  shales  with  occasional 
lenses  of  sand.     Foraminifera  occur 
in  the  lower  part  of  these  shales. 
Some  of  the  sand  lenses  are  highly 
saturated   with   petroleum  and  gas 
under  great  pressure. 
Lenses  occasionally  contain  salt  water. 

Several  oil  wells  yield  production  from 
restricted  sand  lenses  in  this  forma- 
tion. 

1 

s 

8 

1 

Cruse  Oil  Zone 

40 

Sand. 
Often  saturated  with  petroleum  and 
gas  under  great  pressure. 
Salt  water  may  occur. 

>       -  .    ,.       -      -••   -                   ' 

This  is  the  most  persistent  oil  horizon 
on  Trinidad,  but  its  thinness,  depth, 
and  violent  gas  pressure  increases  the 
cost  of  exploitation.  It  is  identified 
over  a  large  area  in  the  northern 
portion  of  the  Morne  J'Enfer  Forest 
Reserve  where  it  occurs  1000  to  1200 
ft.  below  the  top  of  the  Stollmeyer  oil 
zone.  Many  of  the  gas-mud  vol- 
canoes of  Trinidad  may  occur  near 
the  outcrops  of  this  horizon. 

o 

0 

S0> 
g 

i° 

Naparima  Clay 

4000 

Clay,    shale,    and    marl    containing 
marine  organic  matter. 
Outcrops    often    with    a    perceptible 
odor    of    kerosene    and    where    an 
irridescent  film  of  oil  covers  pools 
of  water.     Manjak  veins  occur  near 
San  Fernando. 
Commonly    tilted    to    vertical    with 
abrupt  changes  and  overturns. 

Large  areas  outcrop  near    San    Fer- 
nando.    Folding  is  so   complex   and 
abrupt  that  it  is  difficult  to  obtain  a 
reliable  measurement  of  thickness. 
This  formation  may  be  the  "mother 
rock"  from  which  the  petroleum  of 
Trinidad  is  derived. 
Some  of  the  light  oil  from  Trinidad 
may  come  from  wells  in  this  forma- 
tion. 

8 

1 

Clay  and  shale  and  hard  gritty  sand- 
stone. 

Eocene  fossils  occur  in  or  below  the 
Naparima  clay.  The  author  has  not 
made  extensive  studies  of  the 
Tertiary  strata  below  the  Naparima 
clay. 

Unconformity 

Creta- 
ceous 

Dark  ,  black  or  brown  shale  and  lime- 
stone. 

Cretaceous  strata  have  been  reported 
in  limited  areas  in  the  Central  Range 
of  Trinidad  and  doubtfully  farther 
south.  Large  mountainous  areas 
of  Cretaceous  occur  in  Venezuela. 

Unconformity 

Pre-Creta- 

ceous 

Metamor- 
phics 

Schist,    gniess    (Pre-Cretaceous    vol- 
canics  near  Toco). 

The  Northern  Range  of  Trinidad  con- 
sists of  a  metamorphosed  complex 
bounded  on  the  south  by  an  east- 
west  fault  passing  near  Port  of  Spain 
and  Natura  Bay,  and  extending  into 
the  Atlantic  Ocean  and  Venezuela. 

66  PETROLEUM   INDUSTRY   OF   TRINIDAD 

different  fields  are:  0.9524,  0.9722,  0.9589,  0.9459,  0.9333,  0.9211,  and 
0.80942;  or,  17°,  14°,  16°,  18°,  20°,  22°,  and  43°  BaumeV 

Transportation  and  Utilization 

The  Trinidad  Lake  Petroleum  Co.,  Ltd.,  and  the  Petroleum  Develop- 
ment Co.,  Ltd.,  together  operate  a  6-mi.  (9.66  km.)  pipe  line  from  the 
Morne  PEnfer  Forest  Reserve  to  a  tank  farm  at  Brighton  near  Pitch 
Lake  beginning  as  4  in.  (10.16  cm.)  and  increasing  to  10  in.  (25.4  cm.). 
At  Brighton  pier  are  facilities  for  docking  -and  loading  steamers  up  to  35,- 
000  bbl.  in  24  hr.  Much  of  this  oil  has  been  exported  to  the  United 
States  for  industries  using  asphalt  and  its  products. 

The  Trinidad  Leaseholds,  Ltd.,  operates  approximately  28  mi.  (45 
km.)  of  6-in.  (15.24  cm.)  pipe  line  from  the  Morne  PEnfer  Forest  Reserve 
to  Pointe  a  Pierre,  with  a  short  side  branch  from  Barracpore.  At  Pointe 
a  Pierre  is  a  tank  farm  and  pipe  trestles  to  a  loading  station  1  mi.  (1.6 
km.)  from  shore  where  full-size  tank  steamers  can  be  loaded.  Most  of 
this  oil  has  been  taken  by  the  British  Admiralty,  although  considerable 
has  been  disposed  of  as  bunker  fuel  to  steamships  and  some  has  been 
refined  at  Pointe  a  Pierre. 

The  United  British  Oilfields  of  Trinidad,  Ltd.,  operates  a  6-in.  (15.24 
cm.)  pipe  line  6  mi.  (9.66  km.)  in  length  from  the  Morne  PEnfer  Forest 
Reserve  to  Point  Fortin,  with  an  additional  branch  contemplated.  At 
Point  Fortin,  oil  is  loaded  in  barges  and  towed  to  tankers  anchored  in 
the  Gulf  of  Paria.  Loading  a  tanker  requires  several  days.  A  refinery 
at  Point  Fortin  produces  "  navy  fuel."  Most  of  this  oil  has  been  taken  by 
the  British  Admiralty,  but  some  of  it  has  been  disposed  of  as  bunker  fuel 
oil  to  steamships  and  some  early  shipments  went  to  various  places. 

The  Trinidad  Central  Oilfields,  Ltd.,  operates  a  3-in.  (7.62  cm.) 
pipe  line  from  the  Tabaquite  oil  field  to  a  loading  pier  at  Claxtons  Bay. 
This  oil  is  very  high  in  gasoline  and  is  nearly  all  refined  for  petrol,  kero- 
sene, and  fuel  residue. 

Stollmeyer,  Ltd.,  operates  a  2-in.  pipe  line  2  mi.  (3.22  km.)  in  length 
from  near  the  Morne  PEnfer  Forest  Reserve  to  Guapo  Bay  where  sail 
lighters  can  be  loaded. 

FUTURE  POSSIBILITIES 

The  future  of  the  petroleum  industry  of  Trinidad  depends  on  the 
discovery  of  new  oil  fields  or  units  as  much  as  on  complete  exploitation 
of  the  known  fields.  The  most  obvious  oil  fields  are  already  in  exploi- 
tation. The  writer  is  confident  that  a  thorough  search  will  result  in 
the  discovery  of  other  oil  fields  which  will  compare  favorably  with  the 
known  fields. 


DISCUSSION  67 

The  discovery  of  new  oil  fields  necessitates  the  drilling  of  isolated  test 
wells  of  which  most  will  be  barren.  Exploratory  drilling  should  be  guided 
by  a  thorough  geological  study  of  a  broad  area  with  special  attention  to : 
The  magnitude  and  trend  of  the  unconformity  below  the  Morne  PEnfer 
formation,  character  of  strata  below  this  unconformity,  and  geologic 
folding.  Such  geological  study  will  reduce  the  number  of  barren  wells, 
which  is  the  greatest  expense  of  exploration.  In  the  known  fields  a 
continuous  drilling  program  will  be  necessary  to  maintain  the  production 
with  declining  wells. 

DISCUSSION 

RALPH  ARNOLD,  Los  Angeles,  Calif. — The  Trinidad  field  has  been  the 
graveyard  of  the  reputation  of  many  drillers  and  production  men.  Ap- 
parently the  effort  to  hold  back  this  clay  and  sand  by  the  use  of  strainers 
is  unsuccessful  because  the  well  will  gradually  plug  up  to  such  a  point  that 
every  known  method  will  fail  to  loosen  the  pores  and  allow  the  oil  to  come 
in.  As  wells  put  down  near  old  producers  will  show  large  initial  produc- 
tion, the  ultimate  yield  of  oil  will  be  increased  by  putting  down  secondary 
wells. 

In  one  field,  a  perfect  dome,  the  sand  is  in  lenticular  form.  At  first 
the  wells  showed  considerable  water  but  now  the  oil  pumped  is  free 
from  water. 

E.  DEGOLYER,  New  York,  N.  Y. — I  have  understood  that  the  chief 
difficulty  in  Trinidad  operations  was  to  find  any  strainer  that  would  hold 
back  the  sand,  which  is  of  uniformly  fine  grain.  The  ordinary  sand  is 
composed  of  grains  of  assorted  sizes.  The  strainer  lets  the  fine  sand  pass 
through  and  holds  a  sponge  of  the  larger  grains  outside  so  that  after  a  well 
starts  producing,  this  coat  of  larger  grains  on  the  outside  does  as  much 
straining  as  the  strainer  itself. 

R.  VAN  A.  MILLS,  Washington,  D.  C. — It  seems  probable  that  several 
factors  enter  into  the  sanding  up  of  wells.  Underground  changes  in  the 
gravities  and  viscosities  of  the  oils  incident  to  the  operation  of  wells  may 
play  a  part  in  this  trouble.  In  California  there  are  instances  of  the 
Baume*  gravities  of  oils  issuing  from  wells  in  new  fields  undergoing  reduc- 
tions of  7°  in  the  first  months  of  production.  Under  these  conditions  the 
deposition  of  residual  matter  from  the  oils  would  influence  the  sanding 
up  of  the  wells. 

A  more  important  point  is  the  deposition  of  inorganic  matter  (mineral 
salts)  together  with  silt  in  the  sands.  This  induced  effect  is  accomplished 
through  the  agency  of  the  waters  accompanying  the  oils  —concentration 
and  chemical  reactions  being  responsible  for  the  deposition  of  the  salts. 

Water  interferes  with  the  movements  of  the  oils  to  the  wells  espe- 
cially where  the  oils  are  of  high  viscosity.  The  shutting  off  of  the  oils 


68  PETROLEUM   INDUSTRY   OF  TRINIDAD 

through  the  agency  of  waters  is  probably  the  worst  of  these  underground 
troubles  with  which  we  have  to  deal.  I  believe  that  by  reducing  the 
rapid  flows  of  oil  and  gas  we  can  largely  eliminate  these  troubles. 

R.  A.  CONKLING,*  St.  Louis,  Mo. — Mr.  Macready  has  not  made  any 
mention  of  the  Tabagie  field,  which  has  a  very  light  oil,  35°  to  40°,  that 
comes  from  Cretaceous  and  other  sands  much  higher  in  the  Tertiary. 

RALPH  ARNOLD. — In  the  principal  producing  area,  there  is  enormous 
production  during  the  first  three  or  four  days  and  very  light  production 
thereafter.  Many  of  the  wells  have  given  as  high  as  15,000  to  20,000 
bbl.  per  24  hr.  for  the  first  three  or  four  days,  and  but  a  mediocre  produc- 
tion after  that. 

ARTHUR  KNAPP,  Shreveport,  La.— One  other  place  where  the  same 
thing  occurs  is  Louisiana.  The  trouble  is  not  sand  but  squeezing  clay. 
The  clays  in  Trinidad  are  contaminated  with  oil  and  pass  through  the 
perforated  casing.  It  is  useless  to  place  a  screen  for  the  clay  squeezes 
through  and  appears  in  the  overflow  in  the  form  of  paper-thin  sheets. 

E.  DEGOLYER. — I  have  wondered  if  sanding-up  is  not  often  a  case  of 
the  pinching  together  of  top  and  bottom  clays  rather  than  any  blocking  of 
the  well  sand  or  something  of  that  sort.  These  wells,  when  they  come  in 
as  gushers,  produce  large  amounts  of  sand,  so  that  if  all  the  sand  is  blown 
out,  there  is  nothing  to  hold  up  the  overlying  clay  or  mud.  There  must 
be  some  considerable  tendency  for  them  to  close  together  and,  where  the 
sand  had  been  imperfectly  exhausted,  a  small  production  would  continue. 

RALPH  ARNOLD. — We  operated  on  that  theory  at  one  time  and  tried 
to  control  the  flow  of  the  wells  at  the  start,  and  by  holding  back  the  sand 
allowed  the  production  to  be  slower,  but  I  think  the  records  show  that 
the  wells  that  ran  wild  at  the  start  gave  the  greatest  ultimate  production. 

*  Head  Geologist,  Roxana  Petroleum  Co. 


OIL-SHALES  AND   PETROLEUM   PROSPECTS  IN  BRAZIL  69 


Oil-shales  and  Petroleum  Prospects  in  Brazil 

BY  HORACE  E.  WILLIAMS,  A.  M.,*  Rio  DB  JANEIRO,  BRAZIL 

(St.  Louis  Meeting,  September,  1920) 

IN  VIEW  of  the  frequent  occurrence  of  petroleum  in  other  parts  of  the 
world,  it  seems  odd  that  so  large  an  area  as  is  contained  within  the 
borders  of  Brazil  should  be  without  this  product.  This  apparent  de- 
ficiency may  be  due,  however,  to  our  ignorance  of  the  regions  in  which  it 
may  exist.  In  some  places,  indications  point  to  the  probable  existence 
of  petroleum  in  ages  gone  by;  and  while  the  presence  of  petroleum  pools 
may  be  problematic,  in  several  regions  conditions  not  unfavorable  to 
their  occurrence  exist. 

Yet,  Brazil  has  enormous  oil  resources  in  the  rich  oil-shales  in  dif- 
ferent parts  of  the  country.  Many  of  these  shales  are  very  rich  and 
only  suitable  processes  for  the  extraction  of  the  oil  are  lacking.  At  the 
present  time,  only  a  few  small  experimental  plants  are  producing  oil  by 
distillation  from  these  shales.  These  plants  have  been  the  subject  of 
recent  investigations  by  the  Geological  and  Mineralogical  Survey,  a  pre- 
liminary report  of  which  is  in  the  hands  of  the  printer.  The  only  regions 
where  studies  have  not  been  made  are  the  upper  Amazon,  the  Acre,  the 
Rio  Negro,  and  the  Peruvian  frontier,  which  really  seems  to  be  the 
most  promising  field  for  explorations  of  any  in  the  country. 

In  the  vast  plateau  region  of  the  interior  north  of  the  20th  parallel  of 
latitude,  granites,  gneiss,  mica  schists,  and  very  old  metamorphosed 
sedimentaries  predominate.  Later,  sedimentaries  occupy  a  minor  posi- 
tion and,  where  found  in  the  interior,  represent  a  thin  veneering  resting 
on  the  older  rocks.  At  several  places  near  the  coast  they  have  a  greater 
development  and  contain  considerable  beds  of  oil-shale  and  may,  in 
some  cases,  offer  conditions  favorable  for  the  occurrence  of  oil.  Such 
deposits  are  found  in  the  Permian  rocks  of  central  and  southern  Maran- 
hao;  in  the  Tertiary  and  Cretaceous  beds  along  the  coast  of  Alagdas 
Sergipe,  Bahia,  and  perhaps  farther  south  in  Espirito  Santo;  and  in  the 
Parahyba  embayment  north  of  Cape  Frio  and  in  the  interior  Tertiary 
basin  of  eastern  Sao  Paulo. 

*  Geologist,  Brazilian  Geological  and  Mineralogical  Survey.  ' 


70  OIL-SHALES   AND    PETROLEUM   PROSPECTS   IN   BRAZIL 


MARANHAO 

The  information  at  hand  as  to  the  detailed  structure  and  distribution 
of  the  rock  formations  of  this  state  is  very  meager.  It  is  derived  princi- 
pally from  the  paper  by  Dr.  Miguel  Arrojado  R.  Lisboa1  on  the  Permian 
rocks  of  Maranhao  and  from  unpublished  notes  on  these  rocks  in  Piauhy 
and  Maranhao  by  Dr.  Gonzaga  de  Campos,  Director  of  the  Brazilian 
Geological  Survey.  The  Permian  beds  are  exposed  along  the  Rio  Para- 
hyba  for  over  1000  km.  and,  generally,  over  the  southern  and  eastern 
half  of  the  state.  These  beds  are  covered  largely  by  the  thinner  Trias  and 
Cretaceous  formations.  In  the  extreme  northwestern  part  of  the  state, 
granite  appears  near  the  coast.  While  the  Permian  rocks  have  suffered 
considerable  folding  in  a  minor  way,  the  material  in  hand  seems  to  indi- 
cate a  general  synclinal  structure  across  the  state  with  the  main  axis 
bearing  northeast-southwest. 

On  the  middle  reaches  of  the  Itapicuru  and  Mearim  Rivers,  bitu- 
minous shales  are  found  together  with  calcareous  sandy  and  marly  beds 
associated  with  limestones.  Occurrences  are  also  met  with  near  Cod6 
on  the  Itapicuru,  on  the  Rio  do  Inferno,  at  Fazenda  da  Uniao  on  the 
Igarape  Sant'Anna,  on  the  Codosinho,  and  on  the  Rio  Mearim  at  the 
city  of  Barra  da  Corda. 

At  the  occurrence  on  Rio  do  Inferno,  the  beds  strike  east  and  west 
with  a  dip  of  30°  south.  The  lowermost  bed  consists  of  a  bog-head  coal, 
somewhat  similar  to  the  Marahii  beds  of  Bahia,  overlying  a  thick  bed  of 
well-laminated  bituminous  shales.  In  the  bed  of  the  Rio  Mearim,  the 
bituminous  shales  are  covered  by  a  limestone  with  siliceous  and 
gypsiferous  intercalations.  These  beds  have  a  southerly  dip  and 
are  covered  by  over  50  m.  of  flaggy  sandstones.  At  Grajahti, 
farther  southwest,  the  same  gypsiferous  limestone  occurs  but  without  the 
bituminous  shales,  which,  if  present,  are  below  the  water  level  of  the 
river.  The  limestone  dips  northeast  with  the  strike  N.  60°  W.  It  is 
covered  by  a  red  conglomeratic  sandstone.  Similar  beds  are  found  in  the 
extreme  southwest  of  the  state  and  in  northern  Goyaz  on  the  Rio 
Tocantins. 

The  plains  and  lowlands  of  central  Maranhao  are  so  covered  by  the 
lateritic  formation  that  observations  on  the  underlying  rocks  are  difficult 
especially  as  regards  character  and  structure.  Field  work  in  this  region 
is  practicably  limited  to  the  dry  season,  from  May  to  November.  Samples 
of  the  oil-shale  from  this  region  gave  the  following  results  on  analysis: 
bitumen,  36.5  per  cent. ;  clays,  22.6  per  cent. ;  soluble  carbonates,  40.8  per 
cent.;  and  on  slow  distillation  450  1.  (about  100  gal.)  per  ton.  This  ap- 
pears to  have  been  a  very  rich  sample. 

1  Permian  Geology  of  Northern  Brazil.     Am.  JriL.  Sci.  (1914)  37,  425. 


HORACE   E.    WILLIAMS  71 

Some  prospecting  work  has  been  done  in  this  region,  a  drill  having  been 
mounted  near  Cod6,  but  it  seems  that  the  attempt  was  discontinued  after 
considerable  depth  was  attained.  Judging  from  the  registered  dips 
and  strikes  observed  by  different  parties,  the  region  has  suffered  con- 
siderable folding.  For  this  reason  special  work  should  be  done  in 
determining  the  structural  and  stratigraphic  features  before  any  extensive 
drilling  operations  are  undertaken. 

ALAGOAS 

Knowledge  of  this  region  is  obtained  chiefly  from  the  paper  by  Dr. 
John  C.  Branner2  on  the  oil-shales  of  Alagoas.  This  has  been  supple- 
mented somewhat  by  recent  work  on  these  shales  by  the  Service 
Geologico.3  Shales  rich  in  oil  are  found  at  several  places  along  this  coast. 
The  series  of  rocks  to  which  the  oil  shales  belong  are  found  along  the  coast 
about  Cape  S.  Agostinho,  Rio  Formosa,  Tamandare",  Abreu  da  Una,  etc., 
but  at  these  places  the  unweathered  shale  does  not  appear.  Farther 
along  the  beach,  in  latitude  9°  3',  at  Maragogy,  the  oil-bearing  shales 
appear  at  and  a  little  above  tide  level.  At  this  place  they  show  a  wrinkled 
synclinal  structure  and  outcrop  frequently  from  this  point  south,  as  at 
Sao  Bento,  Camax6,  JaparatuM,  and  in  front  of  Pitinguy,  in  latitude  9° 
7',  where  they  are  exposed  at  low  tide.  Dips  are  generally  to  landward. 

At  Barreira  do  Boqueirao,  north  of  the  Porto  das  Pedras,  the  shale 
exposed  has  a  thickness  of  2  m.,  with  a  probable  thickness  of  3  or  4  m.in 
all.  At  Camaragibe,  the  shales  form  a  wave-cut  terrace  about  150  m. 
wide;  the  dips  observed  were  from  5°  to  10°.  At  this  place  several  pits 
were  put  down  many  years  ago.  Samples  from  these  pits  examined  by 
Boverton  Redwood4  showed  the  following  composition: 

PEE  CENT.  PEK  CENT.  PER  CENT.  PER  CENT.  PER  CENT. 

Volatile 30.6  24.8             27.1             25.5  7.8 

Non-volatile  combustible...     9.5  4.3               2.2               2.2  2.9 

Ash 60.0  70.9             80.7             72.3  89.3 

The  shales  are  exposed  at  Barra  do  Santo  Antonio  and  at  Riacho  Doce 
in  latitude  9°  36'.  The  exposure  at  Riacho  Doce  is  quite  similar  to  those 
already  mentioned.  Several  pits  were  sunk  and  the  shales  were  found 
to  be  richer  than  those  at  Camaragibe.  The  composition  was  as  follows: 


Pi 
Volatile 

:R  CENT. 
34  9 

PER  CENT. 
46  3 

PER  CENT. 
26.9 

PER  CENT. 
32.8 

PERCENT. 
25.4 

Non-volatile  combustible.  . 
Ash  .  .  . 

.     1.1 
64  0 

19.5 
34  2 

8.1 
65  0 

14.6 
52.6 

10.5 
64.1 

2  Oil-bearing  Shales  of  the  Coast  of  Brazil.     Trans.  (1900)  30,  537. 

'Gonzaga  de  Campos:  "Informacoes  sobre  a  Industria  Siderurgica."  Rio  de 
Janeiro,  1916. 

4  Boverton  Redwood  and  William  Topley:  "Report  on  the  Riacho  Doce  and 
Camaragibe  Shale  Deposits  on  the  Coast  of  Brazil  near  Macei6."  London,  1891. 


72  OIL-SHALES   AND   PETROLEUM   PROSPECTS   IN  BRAZIL 

A  further  examination  of  the  second  sample  showed  4.7  per  cent, 
sulfur,  and  upon  distillation  it  yielded  44.73  gal.  of  oil  and  19.58  gal.  of 
ammoniacal  water  per  ton.  Exposures  of  these  rocks  are  met  with  10  or 
15  km.  inland  in  some  of  the  river  valleys  and  along  the  railway . 

Redwood  says  of  these  shales:  "The  presence  of  sulfur  would  not, 
however,  be  a  serious  objection,  if  the  crude  oil  were  used  as  a  liquid  fuel 
or  as  a  source  of  gas  for  illuminating  purposes.  One  ton  of  such  oil  would, 
if  properly  burned,  afford  rather  more  heat  than  two  tons  of  good  steam 
coal,  and  from  each  gallon  of  oil  about  90  cu.  ft.  of  60  candlepower  gas 
could  be  produced.  Results  obtained  on  the  laboratory  scale  of  working 
are  less  satisfactory  than  those  obtained  when  the  shale  is  distilled  on  the 
manufacturing  scale  in  retorts  of  suitable  construction.  The  difference 
is  far  greater  in  the  case  of  the  ammoniacal  liquor,  and  a  yield  of  probably 
four  times  the  quantity  of  sulfate  of  ammonia  may  be  expected." 

BAHIA 

The  better  known  occurrences  of  bituminous  rocks  in  this  state  are 
those  found  in  the  vicinity  of  Marahti  and  southwards  along  the  coast. 
The  best  study  of  the  Marahti  deposits  is  to  be  found  in  the  paper  by  Dr. 
Gonzaga  de  Campos,6  who  examined  the  region  in  the  year  1902.  These 
rocks  occur  along  the  coast  in  the  flat  region  for  considerable  distances  and 
widths.  The  Marahu  deposits  are  about  30  km.  long  by  about  15  km. 
wide.  The  beds  contain  both  fresh-water  and  marine  fossils.  Resting 
up  against  the  old  crystalline  rocks  is  a  fresh- water  series  of  rocks  contain- 
ing plant  remains,  which  is  largely  impregnated  with  bituminous  matter. 
This  is  characteristic  of  the  western  inland  part  of  the  basin.  Farther 
east,  resting  on  these  beds,  are  found  limestones  containing  marine  fossils 
and  also  with  impregnations  and  masses  of  asphalt;  these  beds  are  of 
Cretaceous  age. 

The  appearance  of  the  bituminous  and  carbonaceous  material  every- 
where is  notable;  these  materials  occur  in  the  most  varied  forms.  In 
these  beds  are  found  large  solid  impregnations  having  the  appearance  of 
asphalt;  at  some  points  the  bitumen  is  viscous  like  pitch.  At  Taipu- 
mirim,  cavities  a  meter  or  more  in  diameter  and  quite  deep  are  filled  with 
black  bituminous  matter.  An  analysis  of  this  material  gave  Dr.  Gonzaga 
de  Campos  the  following:  volatile  matter,  30.0  per  cent.;  non-volatile 
combustible  matter  14.0  per  cent.;  ash,  56.0  per  cent.  The  material 
contains  much  pyrites.  Alcohol  dissolves  little  of  it;  on  evaporation,  it 
gives  a  brown  rosin.  Ether  dissolves  most  of  the  material  and  benzol 
dissolves  it  almost  completely. 

Resting  on  these  Cretaceous  beds,  a  clayey  lignite  is  found  in  the  lower 
beds  of  the  Tertiary  bluff  formation  of  this  coast.  In  the  lowermost 

*  "  Reconhecimento  Geologico  na  Bacia  do  Rio  Merahu,  Bahia."     Sao  Paulo,  1902. 


HORACE   E.   WILLIAMS  73 

beds,  almost  at  tide  level,  the  boghead  coal  known  as  the  "  Turf  a  de 
Marahu"  is  found.  This  is  a  most  peculiar  material,  being  quite  different 
from  other  known  bitumens.  It  is  light  yellow  in  color  with  brown  and 
gray  veins,  which  appear  as  stratification  planes.  The  rock  separates 
along  these  planes  and  frequently  plant  leaves  and  other  fossils  of  vege- 
table origin  are  found.  To  the  touch,  it  is  rather  rough  with  a  felty 
texture.  It  floats  and  does  not  absorb  water  readily.  After  many  days 
immersion,  it  gave  a  density  of  0.925  (mean)  with  variations  between 
0.850  and  1.200.  On  boiling  in  water,  it  becomes  somewhat  elastic  to 
compression.  It  is  easily  cut  with  the  knife  and  is  elastic  to  a  blow  from 
the  hammer,  but  is  readily  reduced  to  a  fine  light  powder.  Neither 
alcohol  nor  ether  dissolves  the  material  but  it  is  highly  bituminous.  It 
takes  fire  readily  from  the  lighted  match  and  burns  with  a  yellow  smoky 
flame.  An  analysis  gave  the  following:  Water  (at  110°),  2.75  per  cent.; 
volatile  matter,  71.65  per  cent.;  non-volatile  combustible  matter,  9.75 
per  cent. ;  mineral  residue,  15.85  per  cent.  The  residue  consists  principally 
of  silica,  much  alumina,  lime,  and  grains  of  quartz.  Beds  of  this 
material  are  exposed  for  a  depth  of  3  to  4  m.  at  the  mouth  of  the  Rio 
Arimembeca  and  are  said  to  continue  in  depth  for  over  15  m.  These 
beds  are  horizontal. 

On  slow  distillation,  this  material  yielded  430  1.  of  crude  oil  to  the 
ton;  the  density  of  this  oil  varies  between  0.870  and  0.880.  Neither  in 
color  nor  aspect  does  the  rock  have  any  resemblance  to  coal,  but  the 
composition  and  the  products  are  those  of  the  bituminous  coals.  It  is 
not  a  bituminous  schist  because  the  organic  material  greatly  predominates 
over  the  mineral.  The  great  mass  of  the  rock  is  composed  of  yellowish 
brownish  humic  material.  By  fractional  distillation,  the  material  gave 
the  following: 

PEB  CENT. 

Below  150°,  water  strongly  charged  with  pyrolignic  acid 10. 00 

Yellow  wine  colored  oil  (sp.  gr.  0.812) 9. 74 

Below  270°,  dark  brown  greenish  oil  (sp.  gr.  0.840) 21 . 84 

Below  350°,  dark  oil  (sp.  gr.  0.884) 5.74 

Residue — coke,  porous,  brilliant,  weak 37. 00 

Loss 15 . 68 

Farther  south  from  Marahu,  in  the  vicinity  of  Ilhe*os,  oil-shales  similar 
to  those  of  Alagoas  are  found  in  several  places.  These  are  small  ex- 
posures of  beds  that  appear  along  the  coast  between  the  granite  points, 
which  hereabouts  frequently  extend  down  to  the  ocean.  The  area  of 
these  beds  seems  to  be  relatively  small;  and  while  they  are  rich  in  oil 
content,  then*  value  remains  to  be  determined.  They  are  under  in- 
vestigation at  the  present  time.  At  one  of  these  exposures,  near  Ilhe'os, 
a  small  still  was  erected,  toward  the  end  of  the  war,  for  the  extraction 
of  oil. 


74  OIL-SHALES    AND    PETROLEUM    PROSPECTS    IN   BRAZIL 

A  region  that  may  prove  of  more  importance  and  worth  while  ex- 
ploring lies  farther  south  to  beyond  Caravellas  in  southern  Bahia  and 
northern  Espirito  Santo.  In  this  region,  over  100  km.  long  by  50  to  80 
km.  wide,  sedimentary  rocks  occur  and  while  no  oil-shale  is  reported,  the 
general  geology  would  indicate  that  it  is  probably  underlain  by  the 
same  shale  horizon  as  that  just  described.  The  deposits  referred  to, 
all  along  the  coast,  outcrop  at  or  near  tide  level;  in  this  region  they  may 
be  slightly  lower  and  so  below  that  level  and  not  exposed  at  low  water, 
for  which  reason  they  have  never  been  observed. 

The  shales  about  Ilhe'os,  as  also  those  of  Alagoas,  on  exposure  after 
quarrying  become  warped  and  separate  out  into  thin  paper-like  sheets. 
These  sheets  burn  readily  and  frequently  contain  beautifully  preserved 
fossil  fish.  Where  more  massive  and  clayey,  the  shales  break  into  blocks 
and  are  not  utilized. 

SAO  PAULO 

The  Tertiary  basin  in  eastern  Sao  Paulo,  on  the  upper  reaches  of  the 
Rio  Parahyba,  is  perhaps  150  km.  long  by  15  to  20  km.  wide.  Over  a 
considerable  part  of  this  basin,  oil-shales  have  been  found.  These 
shales  outcrop  10  to  15  m.  above  the  Parahyba  near  Trememb6  and 
Pindamonhangaba,  where  they  are  being  mined.  Quantities  of  these 
shales  have  been  used  at  the  gas  works  in  Rio  and  in  Sao  Paulo  at  various 
times,  especially  during  the  war,  on  account  of  the  shortage  of  coal. 
There  exists  at  Taubate",  a  small  plant  for  the  distillation  of  oil  from 
these  rocks.  These  shales  also  separate  into  thin  paper-like  sheets  on 
exposure  and  take  fire  readily  from  the  lighted  match.  The  richer  beds 
contain  quantities  of  beautifully  preserved  fossil  fish.  An  analysis  gave 
the  following  composition:  crude  oil,  13.08  per  cent.;  water,  23.36  per 
cent.;  gas  and  loss,  4.02  per  cent.;  mineral  residue,  58.64  per  cent.  On 
slow  distillation  these  shales  yielded  27  gal.  of  crude  oil  per  ton.  How- 
ever, at  the  plant  that  existed  at  TaubatS  many  years  ago,  only  about 
17  gal.  were  extracted. 

SOUTHERN  BRAZIL 

Extending  through  Sao  Paulo,  Parand,  Santa  Catharina,  Rio  Grande 
do  Sul,  and  into  Uruguay6  is  a  very  persistent  bed  of  black  petroliferous 
shale  in  the  upper  Permian  series  of  rocks.  This  bed  of  shale  was  named 
the  Iraty  Black  Shale  by  Dr.  I.  C.  White7  from  its  occurrence  near  the 
station  of  Iraty  on  the  Sao  Paulo  Rio  Grande  railway.  A  freshly  broken 
specimen  of  this  shale  generally  gives  off  a  strong  odor  of  petroleum. 

6  E.  P.  de  Oliveira:  Regioes  Carboniferas  dos  Estados  do  Sul.    Service  Geologico, 
Rio  de  Janeiro,  1918. 

7  "Final  Report  of  the  Brazilian  Coal  Commission."     Rio  de  Janeiro,   1908; 
The  Coals  of  Brazil.     Second  Pan-American  Congress,  1916. 


HORACE   E.   WILLIAMS  75 

At  places,  the  petroleum  of  these  shales  has  been  oxidized  into  al- 
bertite  or  other  substance  resembling  coal,  as  about  Piracicaba  and  Rio 
Claro  in  the  state  of  Sao  Paulo.  Material  rich  in  oil  is  found  between  Sao 
Pedro  and  Piracicaba  in  beds  of  considerable  thickness.  A  company 
has  been  formed  recently  in  the  city  of  Sao  Paulo  for  explorations  in  this 
region.  Near  Rio  Claro,  several  miles  farther  north,  some  drilling  has 
been  done  during  the  last  few  years. 

At  about  the  same  geological  horizon  as  the  above  outcrops,  but  at 
a  much  lower  level,  deposits  of  asphalt  occur  along  the  Rio  Tiete*  near 
Porto  Martins.  Farther  south,  in  the  foot  hills  of  the  Serra  de  Luiz 
Maximo  between  Tatuhy  and  Botucatu,  a  heavy  bed  of  bituminous 
sandstone  is  found  some  distance  above  the  black  shale.  An  analysis 
of  this  rock  showed  15  per  cent,  bituminous  matter.  This  sandstone 
seems  to  represent  the  oxidized  and  eroded  remains  of  a  former  pool. 
Small  deposits  of  asphalt  occur  at  different  places  in  Parand,  and  Santa 
Catharina.  Recently  a  plant  has  been  installed  near  Sao  Gabriel,  in 
Rio  Grande  do  Sul,  for  the  distillation  of  oil  from  these  shales. 

Analyses  of  the  black  petroliferous  shale  and  the  albertite,  as  given  in 
Doctor  White's  report,  are  as  follows: 


PETROLIFEROUS 
SHALE,  PER  CENT. 


Moisture 

Volatile  matter. 
Fixed  carbon . . . 
Ash.. 


Petroline 

Asphaltine 

Non-bituminous  organic  matter. 
Ash.. 


These  black  shales  outcrop  in  the  plains  region  and  among  the  foot 
hills  along  the  east  scarp  of  the  great  interior  plateau.  Farther  south, 
this  scarp  gradually  approaches  the  coast  in  Santa  Catharina  and  then 
swings  back  west  and  southwest  across  Rio  Grande  do  Sul.  The  rocks 
generally  have  a  low  westerly  dip  but  the  whole  region  has  been  some- 
what faulted  and  folded  and  is  cut  by  dikes  of  eruptives  from  which 
extruded  the  great  flows  of  trap  covering  large  parts  of  the  interior. 

The  region  west  of  the  interior  scarp  has  been  indifferently  mapped 
and  almost  no  work  has  been  done  in  studying  the  geological  structure  of 
the  underlying  rocks.  The  region  merits  study.  It  seems  clear  that  no 
pools  are  to  be  expected  east  of  the  mountain  scarp  (the  strata  in  which 
they  might  have  occurred  having  been  removed  by  erosion,  as  near  the 
Serra  de  Luiz  Maximo  above  noted)  but  conditions  may  exist  farther 


76  OIL-SHALES   AND    PETROLEUM    PROSPECTS    IN   BRAZIL 

west  somewhere  in  this  vast  region  favorable  for  the  accumulation  of 
such  pools. 

While  extensive  faulting  and  fissuring  of  the  strata  of  this  region  may 
have  allowed  the  escape  of  contained  petroleum  in  their  vicinity,  these 
are  neither  so  numerous  nor  so  wide  spread  as  to  preclude  its  existence 
in  other  places.  If  one  may  judge  by  many  examples  known  today, 
important  deposits  may  still  be  present  in  the  strata  even  in  the  vicinity 
of  eruptive  dikes.  Be  this  as  it  may  with  regard  to  petroleum,  the  fact 
is  abundantly  demonstrated  that,  in  these  shales,  Brazil  has  an  inex- 
haustible supply  which  .only  requires  suitable  processing  to  become 
available. 

DISCUSSION 

RALPH  ARNOLD,  Los  "Angeles,  Calif. — The  newspapers  state  that  the 
Brazilian  government  is  contemplating  putting  into  effect  rules  and  regu- 
lations for  the  oil  business.  I  think  this  is  a  pretty  good  sign  that  there  is 
oil  in  Brazil. 

DAVID  WHITE,  Washington,  D.  C. — Oil-shales  of  the  Tertiary  age 
have  long  been  known  in  the  Province  of  Bahia.  Bog  heads  extremely 
rich  and  comparable  in  constitution  to  the  "kerosene  shale"  of  New 
South  Wales  are  reported  to  have  been  found  in  the  coal  measures  of 
Santa Catarina  and  Rio  Grande  do  Sul.  Such  Permian  bogheads,  which  I 
examined  at  the  time  Dr.  I.  C.  White  was  investigating  the  Brazilian 
coal  fields,  were,  in  fact,  found  to  be  so  far  identical  paleontologically 
with  the  Australian  rock  as  to  arouse  suspicion  as  to  the  genuineness  of  the 
Brazilian  source  of  the  material,  as  was  noted  in  the  report.  Richly 
bituminous  shales  are,  however,  credibly  reported  to  be  present  in  great 
thickness  in  a  formation  of  Triassic  age  in  Brazil. 

J.  ELMER  THOMAS,  San  Antonio,  Tex. — 1  saw  recently  a  private 
report  on  an  oil-shale  occurrence  in  Santa  Catarina.  While  not  made  by 
a  recognized  expert,  it  was  an  extremely  detailed  and  careful  report  and 
called  attention  to  one  large  deposit  within  100  miles  of  the  coast  and 
midway  between  Buenos  Ayres  and  Rio  de  Janeiro.  Oil  at  this  point 
is  worth  about  $8  per  barrel.  The  deposit  was  believed  to  be  extensive 
and  outcrops  in  a  cliff  to  a  thickness  of  70  ft.  Samples  of  the  oil 
had  been  distilled  in  this  country  and  showed  a  good  gasoline  content 
as  well  as  kerosene,  lubricating  oil,  and  gas  oil.  The  estimated  yield 
was  high,  from  35  to  40  gal.  per  ton.  It  seems  probable  that  an  occur- 
rence of  this  nature  will  be  developed  soon,  as  its  economic  importance 
is  considerable. 

JOHN  C.  BRANNER,*  Stanford  University,  Calif .  (written  discussion). — 
The  theory  of  the  possible  existence  of  oil-bearing  formations  in  the  upper 

*  President  Emeritus. 


DISCUSSION  77 

Amazon  region  is  a  perfectly  legitimate  inference  based  on  the  known  oil- 
bearing  horizon  in  regions  farther  north,  but  it  lacks  the  support  of  all 
the  necessary  facts.  That  region,  however,  is  covered  by  dense  tropical 
forests  and  is  difficult  of  access  on  account  of  its  great  distance  from  the 
coast  and  the  difficult  navigation  of  the  upper  reaches  of  the  Amazon 
River.  Also,  white  races  cannot  remain  in  it  long  with  impunity.  Only 
a  company  with  unlimited  means  could  undertake  the  exploration  and 
exploitation  of  such  an  area.  The  population  is  sparse  and  confined  to  the 
small  towns  along  the  larger  streams. 

In  addition,  the  mining  laws  of  Brazil  do  not  encourage  the  develop- 
ment of  these  regions.  In  Decree  No.  2933,  January,  1915,  article  42, 
paragraph  1  says  that  a  mining  claim  shall  contain  5  hectares  (12.3  acres) 
and  that  the  greatest  number  of  claims  that  may  be  conceded  to  a  single 
individual  or  organization  for  petroleum  is  20  claims  but  "for  the  purposes 
of  mining  operations  the  limits  shall  be  40  claims"  for  petroleum.  I  have 
been  informed  that  efforts  are  being  made  to  revise  the  mining  laws  for 
the  purpose  of  encouraging  the  development  of  that  country's  mineral 
resources  but  I  do  not  know  the  result  of  these  efforts.  A  proposed  new 
mining  law  was  published  at  Rio  de  Janeiro,  Dec.  8,  1917,  but  1  do  not 
know  if  it  was  passed.  This  law  provided  that  the  unit  of  a  claim 
shall  be  a  hectare  but  that  the  number  of  hectares  "  that  may  be  granted 
for  each  type  of  mineral  deposit  shall  be  established  by  the  regulations 
for  the  enforcement  of  this  law."  These  regulations  are  not  published 
with  the  proposed  law. 

No  one  acquainted  with  the  peculiarities  of  petroleum  deposits  of 
other  parts  of  the  world  would  venture  the  large  capital  necessary  in  a 
new  and  untried  field  for  the  sake  of  what  he  could  reasonably  expect  to 
obtain  from  100  acres  of  land. 

Since  the  above  was  written  I  have  received  from  one  of  the  best 
posted  legislators  in  Brazil  the  following  information: 

The  laws  now  in  force  are  those  of  Decree  No.  2933  of  Jan.  6,  1915. 
The  provision  of  Art.  42,  par.  1,  of  that  decree  relating  to  mining  claims 
(lote  de  lavra)  refer  only  to  lands  controlled  by  the  Federal  Government; 
and  inasmuch  as  the  Federal  Government  controls  only  limited  areas, 
this  provision  is  of  little  importance  in  its  bearing  on  petroleum  lands. 
When  considerable  areas  are  required  for  the  development  of  petroleum 
fields,  they  may  be  obtained  from  the  landowners  by  lease  or  purchase 
very  much  as  such  lands  are  secured  in  the  United  States. 


78  INTERNATIONAL  ASPECTS   OF  THE   PETROLEUM   INDUSTRY 


International  Aspects  of  the  Petroleum  Industry 

BY  VAN  H.  MANNING,*  WASHINGTON,  D.  C. 
(New  York  Meeting.'February,  1920) 

IN  SUBSTANCE,  the  international  aspects  of  the  petroleum  industry, 
as  these  relate  to  the  United  States,  are  as  follows:  The  domestic  pro- 
duction is  not  keeping  pace  with  the  domestic  demands;  our  best 
engineering  talent  warns  us  of  the  imminence  of  a  decreased  production  by 
our  oil  wells,  although  more  oil  is  needed;  and  the  only  practical  source 
whence  this  increasing  demand  can  be  supplied  for  some  time  to  come 
will  be  the  foreign  fields.  Other  nations  have  given  thought  to  the  future 
and,  in  recent  years,  have  shown  a  tendency  to  adopt  strong  nationalistic 
policies  regarding  their  petroleum  resources,  policies  that  hinder  or 
prevent  the  exploitation  of  these  resources  by  other  nationals.  In  con- 
sequence, we  find  that,  facing  a  probable  shortage  of  the  domestic  supply, 
our  nationals  are  excluded  from  foreign  fields;  and  this  in  spite  of  the 
fact  that  foreign  nationals  have  been  permitted  to  enter  into  and  exploit 
our  own  oil  resources  on  an  equality  with  American  citizens  and  without 
hindrance  or  restrictions.  This  country  has  supplied  the  larger  part  of 
the  petroleum  consumed  by  the  world  and  yet,  with  a  failing  supply 
imminent,  it  finds  that  those  countries  that  have  been  drawing  upon  our 
resources  to  supply  their  needs  are  showing  a  tendency  to  exclude  us  from 
their  resources.  In  this  way  we  shall  be  transferred  from  a  position  of 
dominence  to  one  of  dependence;  and  only  by  sufferance  of  those  countries 
that  are  now  seeking  financial  or  political  control  of  petroleum  supplies, 
shall  we  be  able  to  obtain  the  oil  we  will  need. 

IMPORTANCE  OF  PETROLEUM 

Petroleum  has  become,  during  recent  years,  one  of  the  essentials 
of  our  social  and  industrial  life.  All  civilized  countries  recognize  that 
the  world  is  dependent  on  petroleum  as  on  nothing  else  except  textiles, 
foodstuffs,  coal,  and  iron.  Today,  the  tendency  is  toward  an  ever- 
increasing  consumption  of  petroleum  and  its  products  as  new  and  more 
efficient  uses  are  found  for  them.  The*utilization  of  petroleum  is  extend- 
ing more  and  more  into  the  structure  of  our  civilization.  Consequently, 

*  Director,  U.  S.  Bureau  of  Mines. 


VAN   H.    MANNING  79 

it  becomes  a  matter  of  the  gravest  concern  whether  we  can  go  on  build- 
ing up  an  industrial  and  social  structure  dependent  on  petroleum  unless 
we  make  provision  for  obtaining  the  necessary  supplies.  Unlike  food- 
stuffs and  textiles,  the  world's  supply  of  petroleum  is  definitely  limited; 
moreover,  it  is,  like  coal  and  iron  resources,  a  wasting  asset.  But  petro- 
leum is  a  liquid,  is  by  nature  migratory,  can  be  quickly  extracted,  and  an 
oil  field  is  readily  exhausted;  whereas  coal  and  iron  are  extracted  more 
slowly  and,  by  prospecting,  reserves  can  be  blocked  out  for  the  years 
ahead.  Oil  fields  once  discovered  are  developed  almost  immediately; 
within  a  short  time  the  peak  of  production  is  passed  and  decline  sets  in. 
We  are  constantly  relying  upon  the  discovery  of  new  fields,  at  the  moment 
unknown,  to  make  up  for  the  decline  and  depletion  of  those  that  are 
proved.  Thus,  we  are  living  a  hand-to-mouth  existence  and  although 
during  the  past  decades  we  have  been  very  fortunate  in  making  opportune 
discoveries — first  Gushing,  then  Kansas,  and  then  northern  Texas — 
each  of  which  has  made  up  for  a  threatened  deficit,  the  time  must  inevi- 
tably come  when  fortune  will  forsake  us  and  the  needed  new  production 
will  not  materialize.  Then  we  may  find  ourselves  suddenly  thrown  upon 
the  mercy  of  the  nations  that  control  foreign  sources  of  supply. 

Few  of  us  realize  in  how  many  ways  petroleum  products  serve  our 
daily  needs.  Petroleum  in  one  form  or  another  is  used  in  every  household ; 
gasoline  for  the  motor  car,  lubricating  oils  for  bearings,  kerosene  lamps  or 
paraffin  candles  for  illumination.  Not  one  of  us  can  sit  back  and  say 
that  an  adequate  supply  of  petroleum  is  not  a  personal  concern.  Perhaps 
a  recent  statement  appearing  from  enemy  sources  may  convey  most  con- 
vincingly the  importance  of  petroleum  in  modern  life.  Ludendorff,  in 
his  book  on  the  late  war,  in  speaking  of  the  Rumanian  campaign,  says, 
"As  I  now  see  clearly,  we  should  not  have  been  able  to  exist,  much  less 
carry  on  the  war,  without  Rumania's  corn  and  oil,  even  though  we  had 
saved  the  Galician  oil  fields  from  the  Russians." 

IMPORTANCE  OF  INDUSTRY 

During  the  world  war,  the  Navy  demonstrated  the  value  of  petroleum 
as  marine  fuel.  Having  a  higher  heating  value  than  coal,  a  given  tonnage 
assures  a  ship  a  much  wider  cruising  range  before  refueling.  In  the 
mercantile  marine  the  smaller  bulk  of  fuel  provides  larger  cargo  space  in 
the  hull.  Cleanliness  and  less  labor  for  loading  and  burning  are  two  other 
important  features.  In  consequence,  new  ships  are  being  built  to  burn 
oil  and  old  vessels  are  being  changed  from  coal  to  oil  burners.  Our 
greatest  maritime  rivals,  the  British,  are  rapidly  equipping  their  merchant 
marine  to  burn  oil,  so  that  it  has  become  obligatory  upon  the  United 
States  Shipping  Board  to  do  likewise  in  order  that  our  vessels  may  be  able 
to  compete  on  an  equal  basis,  as  regards  fuel,  with  foreign-owned  bottoms. 


80      INTERNATIONAL  ASPECTS  OF  THE  PETROLEUM  INDUSTRY 

The  production,  refining,  and  distribution  of  petroleum  and  petro- 
leum products  is  one  of  our  greatest  industries;  it  provides  a  livelihood 
for  many  thousands  of  families.  Although  it  has  offered  a  big  field  for 
the  engineer  and  chemist,  in  my  opinion  it  has  been  comparatively  un- 
exploited  by  the  mining  engineer  and  is  capable  of  absorbing  hundreds,  if 
not  thousands,  of  properly  trained  and  experienced  engineers. 

The  oil  industry  also  provides  a  wonderful  field  for  our  chemical 
engineers.  Petroleum  can  be  considered  as  a  crude  chemical,  like  coal  tar, 
and  the  fuel  value  of  all  its  products  and  the  most  efficient  methods  of 
utilizing  them  have  not  been  discovered  by  any  means. 

Not  only  has  petroleum  furnished  useful  and  essential  products,  but 
industries  based  upon  these  products  rank  among  the  major  activities 
of  the  nation.  Of  such  dependent  industries,  the  greatest  is  the  auto- 
motive industry.  The  automobile,  the  truck,  the  tractor  and  the  air- 
plane enter  into  our  daily  life.  Today  more  than  6,000,000  automobiles 
are  in  use  in  the  United  States  alone. 

The  three  most  important  utilizations  of  petroleum  are  as  fuel,  as  an 
illuminant,  and  as  a  lubricant.  Petroleum  fuels  may  be  classified  as  light 
and  heavy.  The  light  fuels  are  gasoline,  naphtha,  and  kerosene,  which 
can  be  vaporized  and  used  in  the  internal-combustion  engine  of  the  auto- 
mobile or  tractor.  Heavy  fuels  are  those  that  are  burned  directly  for 
steam  raising  or  for  heating  purposes,  or  can  be  used  in  internal-combus- 
tion engines  of  the  Diesel  type.  About  57  per  cent,  of  our  output  of 
crude  petroleum  is  oil  fuel  of  the  heavy  type,  only  a  small  proportion  of 
which  is  used  in  internal-combustion  engines;  the  other  uses  are  relatively 
inefficient  and  for  such  uses  petroleum  is  replaceable  by  coal.  A  larger 
use  of  this  heavy  fuel  in  the  internal-combustion  engine  is  hopefully 
expected,  but  with  this  development,  the  dependence  of  the  world  on 
petroleum  will  be  increased  still  further. 

This  country  is  not  as  dependent  upon  petroleum  illuminants  as  it 
was,  although  kerosene  still  is  used  in  large  quantities  in  districts  not 
served  by  gas  or  electricity,  and  is  an  article  of  great  importance  in  our 
trade  with  foreign  countries. 

Petroleum  lubricants,  although  less  in  amount  than  the  other  prod- 
ucts, are  more  generally  used  and  are  really  more  essential.  They  lub- 
ricate practically  all  bearings  or  moving  parts.  Quantitatively,  there  are 
no  satisfactory  substitutes  and  when  one  starts  to  replace,  on  a  large 
scale,  mineral  lubricants  by  animal  or  vegetable  oils  of  satisfactory  qual- 
ity, the  dependence  of  our  industrial  life  on  petroleum  lubricants  becomes 
evident. 

When  we  realize  what  petroleum,  directly  and  indirectly,  has  done  for 
our  country  and  when  we  try  to  see  what  improvements  in  our  ways  of 
living  the  future  holds  for  us,  the  significance  of  the  international  aspects 
of  the  petroleum  industry  becomes  clearly  evident.  When  we  consider 


VAN   H.    MANNING  81 

the  number  of  automobiles  turned  out  yearly,  the  airplanes  that  will  play 
an  important  part  in  commerce,  the  trucks  that  will  supplement  present 
transportation  facilities,  the  agricultural  machinery  needed  to  meet  the 
lack  of  man  power  on  our  farms,  and  the  relation  of  our  merchant  marine 
program  to  oil,  we  can  understand  how  vitally  necessary  an  adequate 
supply  of  petroleum  will  be  to  us. 

OUR  PETROLEUM  RESOURCES 

The  United  States  was  the  first  country  to  produce  oil  in  large  quan- 
tity by  the  modern  system  of  drilling  wells  and,  except  during  a  few 
years,  has  led  all  the  countries  of  the  world  in  the  quantity  of  its  produc- 
tion. In  1914,  when  the  World  War  began,  the  United  States  was  in 
first  place  and  produced  approximately  266,000,000  bbl.  of  oil,  or 
about  66  per  cent,  of  the  total  output  of  the  world.  Russia  was  second, 
with  an  approximate  production  of  67,000,000  bbl.,  or  about  17  per  cent, 
of  the  world's  total.  Mexico  came  third  with  about  21,000,000  bbl., 
or  a  little  over  5  per  cent,  of  the  world's  production.  Rumania,  the 
Dutch  East  Indies,  India,  Galicia,  Japan  produced  comparatively  small 
amounts  of  oil,  totaling  approximately  12  per  cent. 

In  1914,  therefore,  the  United  States  was  far  ahead  of  any  other 
nation  as  a  producer  of  oil.  It  was  also  far  ahead  of  any  other  in  the 
development  of  its  oil  fields  and  in  the  utilization  of  oil  products.  The 
vital  importance  of  petroleum  had  not  been  fully  recognized  by  the  lead- 
ing countries  of  the  world,  so  the  United  States  occupied  a  unique  posi- 
tion, practically  without  competitors.  Foreign  countries  had  not  begun 
to  consider  seriously  future  supply  and  there  was  less  rivalry  in  gaining 
control  of  possible  oil  fields.  Yet  signs  of  an  awakening  interest  were 
evident.  Great  Britain,  because  of  having  adopted  fuel  oil  in  the  Navy, 
had  begun  taking  steps  to  assure,  through  British  nationals,  an  adequate 
supply  of  oil  from  Mexico  and  to  encourage  development  in  British 
domains.  The  British  Government  had  also  entered  into  partnership 
with  the  Anglo-Persian  Oil  Co.  to  exploit  a  huge  concession  in  Persia. 

The  point  of  real  importance,  however,  is  the  relative  position  of  the 
United  States  as  a  consumer  rather  than  a  producer  of  oil.  To  produce  the 
bulk  of  the  world's  production  is  of  small  consequence  in  comparison  with 
producing  enough  to  meet  our  present  and  probable  future  needs.  In 
1918,  the  output  of  crude  oil  in  the  United  States  was  356,000,000  bbl. 
Mexico  had  taken  second  place  with  63,000,000  bbl.  The  production  of 
the  United  States  for  the  past  several  years  has  been  approximately  65 
per  cent,  of  the  world's  total.  The  approximate  consumption  of  the 
United  States  for  the  year  1918  was  418,000,000  bbl.,  or  more  than  80 
per  cent,  of  the  world's  production.  This  figure  of  consumption,  however, 
includes  the  oil  that  was  refined  or  partly  refined  in  the  United  States  and 

VOL.  LXV.— 6 


82      INTERNATIONAL  ASPECTS  OP  THE  PETROLEUM  INDUSTRY 

exported  for  consumption  abroad.  The  exports  of  petroleum  products 
approximated  the  imports  of  crude  petroleum  from  Mexico  and  other 
foreign  countries.  But  in  addition,  some  20,000,000  bbl.  of  oil  were 
withdrawn  from  domestic  storage.  In  substance,  therefore,  the  United 
States,  in  1918,  was  living  beyond  its  means.  The  year  1919,  because  of 
the  present  flush  production  from  Texas  fields  and  the  increased  imports 
from  Mexico,  finds  the  United  States  in  a  somewhat  more  favorable  condi- 
tion, not  having  to  draw  on  stocks;  yet  it  must  be  remembered  that  the 
stocks  have  not  only  decreased  actually  but  have  decreased  in  proportion 
to  our  production  and  consumption.  Thus,  in  1915,  there  was  over  six 
months'  supply  of  oil  in  storage,  whereas  at  the  end  of  1918  stocks  had 
been  reduced  to  less  than  four  months'  supply. 

The  U.  S.  Geological  Survey  has  given  the  following  figures  of  the  mar- 
keted production  and  consumption  in  the  United  States.  The  figures 
for  marketed  production  approximate,  but  are  not  the  same  as,  actual 
production: 

MABKETED  PRO-  CONSUMPTION, 

DUCTION,  BARRELS  BARRELS 

1916 301,000,000  329,000,000 

1917 335,000,000  384,000,000 

1918 356,000,000  418,000,000 

i 

Evidently  the  production  of  the  United  States,  in  spite  of  its  having 
risen  steadily  during  recent  years,  is  not  rising  as  rapidly  as  it  should  and 
is  not  keeping  pace  with  the  increase  in  consumption.  The  sources  from 
which  we  can  draw  for  our  future  needs  of  petroleum  and  its  products  are : 
Our  own  oil  fields,  foreign  oil  fields,  oil  shales,  and  substitutes  for  petro- 
leum products.  Engineers  and  geologists  who  have  investigated  the 
possible  oil  underground  in  our  developed  and  undeveloped  oil  fields 
agree  in  making  pessimistic  reports.  This  is  particularly  true  of  the  U.  S. 
Geological  Survey,  the  organization  that  has  given  most  attention  to  our 
petroleum  resources  and  has  the  most  facts.  The  U.  S.  Geological  Sur- 
vey estimates  our  unproduced  but  recoverable  oil  in  January,  1919,  at 
6,740,000,000  bbl.  This,  could  it  be  produced  as  needed,  would  not  con- 
tinue our  present  production  of  oil  for  more  than  20  years. 

Many  persons,  especially  non-technical  oil  men,  are  inclined  to  ques- 
tion these  estimates  and  call  them  too  pessimistic,  saying  that  whenever 
in  the  past  more  oil  was  needed  new  discoveries  were  made  and  unexpected 
fields  brought  forth  new  supplies.  However,  our  best-informed  engineers 
have  given  this  estimate,  and  their  belief  should  outweigh  the  vague  optim- 
ism of  those  who  question  it.  Of  course,  in  view  of  the  fallibility  of  estimates, 
the  figures  may  prove  to  be  too  pessimistic.  Even  if  the  estimates  of  the 
supply  of  unrecovered  petroleum  were  50  to  100  per  cent,  too  low,  the 
situation  would  still  not  be  satisfactory.  And  the  fact  remains  that  no 


VAN   H.    MANNING  83 

matter  how  much  oil  there  may  still  be  in  the  ground,  we  have  not  been 
and  are  not  getting  it  to  the  surface  as  fast  as  it  is  now  needed. 

Clearly,  we  must  seek  other  sources  of  supply  to  make  up  the  balance 
between  domestic  production  and  domestic  needs.  Enormous  deposits 
of  oil-bearing  shales  occur  in  the  western  states,  in  the  Cretaceous  forma- 
tions of  the  Rocky  Mountain  region.  The  U.  S.  Geological  Survey  esti- 
mates that  the  shales  in  the  states  of  Colorado,  Wyoming,  and  Utah  alone 
contain  many  times  the  recoverable  oil  present  in  our  oil  fields  before  well 
drilling  began.  But  the  oil  in  these  shales  is  not  immediately  available. 
The  extraction  of  oil  from  the  shales  on  a  commercial  scale  under  existing 
conditions  in  the  United  States  is  still  in  an  experimental  stage.  We  do 
not  know,  as  yet,  whether  these  shales  can  be  developed  profitably  under 
present  conditions,  nor  under  what  conditions  they  can  be  developed. 
Furthermore,  it  will  take  many  years,  even  under  favorable  conditions, 
to  obtain  from  these  shales  enough  oil  to  replace  a  considerable  part  of 
that  now  obtained  from  wells. 

I  do  not  wish  these  statements  to  be  interpreted  as  reflecting  on  the 
prospects  of  the  shale  industry,  but  simply  wish  you  to  realize  that  the 
production  of  oil  in  the  quantities  demanded  by  present-time  needs  would 
require  development  on  a  tremenduous  scale  and  would  require  the  mining 
of  hundreds  of  millions  of  tons  of  shale  each  year,  the  annual  amount 
being  more  than  half  the  annual  tonnage  of  coal  now  mined.  There  is 
no  evidence  that  shale  oil  can  be  produced  on  such  a  scale  at  present  prices 
and,  therefore,  to  satisfy  our  petroleum  needs  by  oils  from  shales  involves 
higher  prices  for  petroleum  products.  Moreover,  our  oil  shales  occur  in 
sparsely  populated  regions,  remote  from  centers  of  large  consumption. 
Oil  shales  constitute  a  reserve  that,  fortunately,  seems  to  provide  ample 
protection  against  an  ultimate  future  but  they  cannot  be  used  to  meet 
the  present  situation. 

SUBSTITUTES 

The  products  from  the  destructive  distillation  of  coal  can  be  used, 
in  so  far  as  they  are  available,  to  replace  gasoline;  but  quantitatively  it 
seems  out  of  the  question  to  expect  more  than  a  minor  alleviation  from 
them.  Coal  can  largely  replace  fuel  oils.  Alcohol  can  replace  gasoline 
and  has  the  advantage  that  it  can  be  made  from  replaceable  material— 
that  is,  from  plants,  but  because  of  its  cost,  it  cannot  compete  in  a  large 
way  with  gasoline  at  present.  Moreover,  the  difficulty  and  expense  of 
replacing  any  considerable  part  of  the  gasoline  supply  by  alcohol  is  not 
generally  appreciated.  Finally,  no  substitutes  are  now  known  that  will 
satisfactorily  replace  mineral  lubricants  in  the  quantities  needed. 

Thus,  the  facts  indicate  that  we  must  inevitably  seek  foreign  supplies 
in  order  to  meet  our  needs  and  to  compete  in  the  world's  markets  with- 


84  INTERNATIONAL   ASPECTS   OF  THE   PETROLEUM   INDUSTRY 

out  too  great  a  handicap.  However,  we  should  not  rely  upon  any  one 
solution  of  the  problem,  but  should  seek  to  put  into  effect  every  feasible 
means  that  promises  to  help,  and  should  strive  to  anticipate  our  future 
needs  rather  than  to  go  along  blindly  with  the  inevitable  result  of  sud- 
denly being  confronted  at  some  future  date  with  a  shortage  of  oil.  Steps 
should  be  taken  to  conserve  our  developed  supply.  This  supply  is  tangi- 
ble; we  already  have  it,  and  common  sense  dictates  that  we  take  the  best 
possible  care  of  it.  By  conservation  I  do  not  mean  the  tying  up  of  re- 
sources, but  a  wise  utilization,  the  working  out  of  methods  that  will 
yield  us  the  greatest  quantity  of  oil  at  the  least  cost  and  will  enable  us 
to  refine  and  use  the  oil  with  the  highest  efficiency.  This  phase  of  the 
question  is  peculiarly  a  part  of  the  work  of  technical  men,  and  I  believe 
that  this  Institute  should  seriously  endeavor  to  further,  in  every  possible 
manner,  the  application  of  engineering  methods  to  the  oil  business,  for 
the  oil  industry  is  probably  more  backward  in  applying  engineering 
knowledge  than  any  other  mineral  industry.  This  statement  is  not  a 
criticism  of  the  oil  industry  for  being  backward  in  taking  up  engineering, 
any  more  than  it  is  a  criticism  of  the  engineer  in  being  backward  in  taking 
up  the  oil  industry.  Until  recently  there  were  few  engineers  who  were 
qualified,  by  actual  experience  in  the  oil  fields  as  well  as  by  engineering 
training,  to  be  of  real  assistance  to  the  industry.  Happily,  this  condition 
is  rapidly  improving.  Yet  there  is  today  an  under  supply  of  competent 
petroleum  engineers  equipped  to  deal  with  practical  problems. 

In  addition,  we  should  further  the  oil-shale  industry  and,  regardless 
of  our  individual  opinions,  should  endeavor  to  determine  as  soon  as  pos- 
sible under  what  conditions  the  oil-shale  industry  is  commercially  feasible, 
and  thus  be  prepared  for  a  future  emergency. 

In  the  same  way,  petroleum  substitutes  should  not  be  neglected 
These  lie  mainly  in  the  field  of  the  chemical  engineer  rather  than  of  that 
the  mining  engineer. 

FOREIGN  SOURCES  OF  SUPPLY 

Recently,  the  U.  S.  Geological  Survey  has  shown  a  particular  interest 
in  questions  of  foreign  supply,  and  has  rendered  a  splendid  public  service 
by  collecting  all  possible  information  on  the  subject.  This  information 
has  been  placed  at  the  disposal  of  the  government  and  also  of  those  in- 
dividuals who  contemplate  entering  foreign  fields.  . 

In  the  opinion  of  the  U.  S.  Geological  Survey,  enormous  resources 
await  development  in  various  parts  of  the  world;  but  these  resources  have 
not  been  developed  as  intensively  as  those  of  the  United  States.  The 
premier  position  of  the  United  States  to  the  present  time  has  been  due, 
perhaps,  more  to  an  intensive  development  of  resources  than  to  any 
supremacy  in  the  resources  themselves.  Enough  information  is  available 
about  foreign  countries  to  know  that  oil  occurs  in  many  places,  and  that 


VAN   H.    MANNING  85 

there  are  partly  developed  fields  of  high  promise.  It  may  well  be  that 
in  vast  areas  which  have  not  been  studied  by  the  geologist  or  tested  by 
the  prospector  there  are  undiscovered  fields  of  great  magnitude.  For 
these  reasons  I  believe  that  there  is  not  nearly  as  much  danger  of  a  world 
shortage  as  there  is  of  a  domestic  shortage.  Fortunately,  the  situation 
requires  nothing  more  than  the  developing  of  foreign  fields  as  supplies  are 
needed  and  the  accessibility  of  those  fields  to  our  nationals.  The  problem 
that  presents  itself,  therefore,  is  whether  the  United  States  can  obtain 
an  adequate  share  of  oil  from  the  known  and  potential  fields  of.  the  world, 
or  whether  it  is  going  to  be  excluded  by  the  political  and  economic  policies 
of  other  nations  and  thus  find  itself,  so  far  as  petroleum  is  concerned,  at 
the  mercy  of  those  nations. 

The  key  to  the  future  is  access  to  the  sources  of  supply.  The  strong 
financial  position  of  the  petroleum  industry,  in  this  country,  the  refining 
and  marketing  facilities  of  the  strongest  American  companies  will  not, 
by  themselves,  suffice  if  we  are  at  the  mercy  of  the  citizens  of  other  nations 
for  our  crude  supplies. 

STRONG  NATIONALISTIC  TENDENCY  OF  FOREIGN  COUNTRIES  TO 
EXCLUDE  OTHER  NATIONALS 

One  result  of  the  war  has  been  an  accentuation  of  nationalistic  spirit; 
the  nations  that  were  combatants  and  those  that  were  neutral  have  shown 
increasingly  a  tendency  to  exclude  other  nationals  from  their  domains  and 
to  develop  their  own  resources  by  their  own  interests.  This  tendency  is 
a  natural  result  of  an  awakened  knowledge  of  the  need  of  self -protection 
and  of  a  desire  to  conserve  for  themselves  the  materials  now  essential  to 
the  world's  civilization. 

The  United  States  is  not  an  imperialistic  nation,  and,  exclusive  of 
Alaska,  its  foreign  possessions  are  with  small  potential  resources.  Thus 
we  find  no  political  control  of  consequence  over  other  than  the  domestic 
sources  of  supply  within  the  United  States  proper. 

When  we  turn  to  the  developed  or  prospective  oil  fields  in  other  parts 
of  the  world,  we  find  that  their  political  control  may  be  grouped  under  two 
heads:  colonies  and  domains  of  such  nations  as  England  and  France, 
and  domains  of  smaller  nations,  such  as  the  Latin-American  countries, 
China  and  Persia;  under  present  chaotic  conditions  perhaps  Russia  could 
be  included.  The  most  promising  oil  districts  now  known  outside  of  the 
United  States  are  in  Mexico,  in  the  South  American  countries  bordering 
the  Caribbean,  in  Equador,  Peru,  Bolivia,  Argentina,  northern  Africa, 
Egypt,  Persia,  Mesopotamia,  Palestine,  Russia,  India,  East  Indies,  and 
China.  There  are  other  localities  of  smaller  promise  or  about  which  less 
is  known,  and  doubtless  some  of  these  will  develop  fields  of  the  first 
magnitude  when  explored  and  prospected. 

When  one  reviews  these  potential  oil  fields,  one  is  struck  with  the 


86      INTERNATIONAL  ASPECTS  OP  THE  PETROLEUM  INDUSTRY 

fact  that  Latin  America,  Great  Britain,  France,  and  the  Netherlands, 
apparently  control  the  main  potential  sources  of  supply,  and  particularly 
those  that  are  of  the  most  concern  to  the  United  States.  Thus,  the  poli- 
cies of  these  countries  are  of  the  greatest  interest  to  America.  We  find 
England  and  France  adopting  policies,  already  in  part  incorporated  into 
laws  or  regulations,  that  now  virtually  exclude  other  than  their  own 
nationals  from  developing  the  resources  within  their  own  realms.  Of 
course  I  do  not  mean  to  insinuate  that  the  policies  of  these  countries  are 
aimed  directly  at  Americans;  the  policy  of  each  country  is  to  look  after 
its  own  citizens;  hence  it  is  directed  against  the  citizens  of  all  other 
countries,  and  thus  affects  Americans.  For  a  detailed  statement  regard- 
ing the  policies  of  these  countries  I  refer  to  a  memorandum  by  myself 
to  the  President,  which  was  disclosed  to  the  United  States  Senate  by  Sena- 
tor Phelan  of  California.  Copies  of  this  document  appear  in  the  Con- 
gressional Record  of  July  29,  1919.  Those  interested  in  the  various 
political  phases  of  the  situation  can  obtain  information  there,  or  from  the 
American  Petroleum  Institute. 

The  members  of  this  Institute  are  well  informed  as  to  the  situation  in 
Mexico.  Mexico  is  considering  stringent  regulations  as  to  oil  concessions 
which,  if  enacted  into  law  will  be  very  detrimental  to  the  just  interests  of 
nationals  other  than  Mexicans,  including  ourselves.  The  policy  of 
Argentina  has  been,  practically,  the  nationalization  of  its  petroleum  re- 
sources. Other  Latin-American  countries  have  shown  some  uncertainty 
as  to  what  their  policies  are  to  be.  Japan  has  adopted  a  policy  that 
practically  excludes  other  nationals  from  its  own  fields  in  Japan,  Formosa, 
the  Island  of  Sakhalin,  and  from  the  fields  of  China  so  far  as  its  control 
extends.  The  Netherlands  Government  has  also  adopted  a  policy  of  ex- 
clusion that  practically  restricts  developments  within  its  domains  to  its 
own  nationals.  France  has  adopted  policies  that  are  not  so  evident  on 
the  surface,  but  in  effect,  these  policies  are  proving  restrictive,  and  are 
seemingly  intended  to  exclude  other  nationals. 

RECIPROCAL  PRIVILEGES  SHOULD  BE  GIVEN  TO  AMERICAN 

NATIONALS 

A  review  of  the  foreign  situation,  therefore,  discloses  the  fact  that 
whereas  other  nationals  can  enter  our  oil  fields,  acquire  properties  there, 
and  work  these  properties  on  an  equality  with  ourselves,  our  nationals 
are  not  receiving  reciprocal  privileges  from  many  foreign  governments 
now  controlling  the  most  important  oil  regions  of  the  world,  and  thus  in 
time  we  are  likely  to  be  largely  dependent  on  those  governments  for  our 
domestic  needs.  Moreover,  conditions  in  the  Latin-American  countries 
are  not  as  satisfactory  as  they  might  be.  The  question  comes,  therefore, 
as  to  what  should  be  done  toward  removing  discrimination  under  which 
Americans  are  practically  excluded  from  foreign  oil  fields.  It  is  not  for 


DISCUSSION  87 

me  to  discuss  here  such  a  question  in  detail,  but  it  is  perfectly  obvious 
that  in  all  fairness  our  nationals  should  be  accorded  the  same  privileges 
that  we  accord  other  nationals.  It  has  not  been  the  policy  of  the  United 
States  to  exclude  foreign  corporations  or  individuals;  in  fact,  they  have 
been  welcomed,  as  it  has  been  recognized  that  the  capital  brought  in  has 
been,  in  a  large  way,  helpful  to  the  United  States  even  though  the  profits 
went  mostly  to  the  benefit  of  other  nationals.  It  would  be,  in  my  opin- 
ion, a  mistake  to  forsake  this  policy,  just  as  I  believe  it  is  a  mistake  on 
the  part  of  other  nationals  to  have  put  into  effect  such  policies.  It 
would  be  desirable  if  all  countries  adopted  the  same  open  policy  as  that 
which  has  prevailed  in  the  United  States. 

In  regard  to  individual  Americans,  and  particularly  to  the  members 
of  this  Institute,  it  seems  to  me  that  it  is  the  duty  of  all  to  interest  them- 
selves in  the  situation  and  to  do  what  they  can  to  educate  the  people  of 
this  country  and  their  representatives  as  to  the  situation,  and  to  urge 
such  wise  and  necessary  steps  as  would  best  relieve  it. 

Another  help  that  the  members  of  this  Institute  can  render  is  to 
transmit  to  the  government  such  information  as  it  acquires  on  the  foreign 
situation,  including  information  on  the  possibilities  of  oil  fields,  on  laws, 
regulations,  and  policies  that  tend  to  discriminate  against  American 
nationals  entering  foreign  fields,  and  on  actual  cases  of  discrimination. 
This  information  built  up  from  many  sources  will  prove  invaluable  to  the 
government,  and  thus  to  yourselves  and  those  interested  in  the  foreign 
oil  fields.  I  do  not  know  whether  the  furtherance  of  such  work  could  be 
made  properly  a  part  of  this  Institute  collectively,  but  I  see  no  reason  why 
the  members  of  this  Institute  should  not  render  this  service  to  their 
government. 

I  may  also  urge  the  opportunities  and  national  importance  of  Ameri- 
can concerns  entering  foreign  oil  fields.  Evidently  this  country  is  going 
to  need  foreign  sources  of  supply,  and  it  will  be  to  its  great  advantage  to 
obtain  these  through  its  own  nationals.  Heretofore,  American  methods, 
American  machinery,  American  brains  have  been  employed  by  foreign 
capital  to  develop  foreign  resources.  It  will  be  more  desirable  if  our 
brains  and  abilities  are  employed  under  our  own  nationals.  It  is  desir- 
able that  every  engineer  realize  before  accepting  employment  with  any 
foreign  corporations  competing  against  ours,  just  what  this  means.  I 
believe  it  should  be  made  a  policy  of  the  members  of  this  Institute  to  see 
that  the  younger  engineers  and  those  unacquainted  with  foreign  condi- 
tions, are  informed  on  this  matter. 

DISCUSSION 

LEONARD  WALDO,  New  York,  N.  Y. — In  Mexico,  there  are  huge  oil 
resources,  but  the  only  means  of  transmitting  that  oil  to  the  United 
States  is  by  ship,  and  ships  seem  to  be  forgotten  on  all  occasions.  Those 


88      INTERNATIONAL  ASPECTS  OF  THE  PETROLEUM  INDUSTRY 

we  had  at  the  beginning  of  the  war  for  carrying  oil  were  almost  all  under 
foreign  charters,  which  were  soon  recalled  and  the  ships  used  for  trans- 
porting oil  from  Mexico  and  other  points  to  Europe.  Consequently,  now 
we  have  a  scarcity  of  ships  for  carrying  oil ;  that  is  the  most  important 
defect  in  fueling  the  Atlantic  seaboard.  Every  effort  should  be  made  to 
bring  the  shipping  interests  into  line,  including  the  government  shipping. 
Oil  is  the  one  way  of  fueling  the  Atlantic  seaboard  and  taking  care  of 
our  steel  plants,  our  boiler  plants,  our  heavy  industries  that  take  oil, 
and  ships  must  be  used  to  relieve  the  pressure  from  the  oil  lines,  which 
are  only  capable  of  supplying  the  higher  uses  of  oil  at  20  or  30  cents  a 
gallon.  For  fuel,  the  marketable  value  of  oil  should  be  about  2  cents  a 
gallon;  before  the  war,  large  contracts  were  made  at  1.8  cents  per  gallon 
for  Mexican  fuel  oil  delivered  at  the  docks  for  the  steel  works  to  use. 


A   FOREIGN    OIL   SUPPLY   FOR  THE   UNITED   STATES  89 


A  Foreign  Oil  Supply  for  the  United  States 

BY  GEORGE  OTIS  SMITH,*  PH.  D.,  WASHINGTON,  D.  C. 

(New  York  Meeting,  February,  1920) 

TWELVE  years  ago,  the  Director  of  the  United  States  Geological  Sur- 
vey addressed  to  the  Secretary  of  the  Interior  a  letter  calling  attention  to 
the  government's  need  for  liquid  fuel  for  naval  use  and  pointing  out  that 
the  rate  of  increase  in  demand  was  more  rapid  than  the  increase  in  pro- 
duction.1 This  letter,  in  a  way,  inaugurated  the  policy  of  public  oil- 
land  withdrawals,  which  was  well  founded  in  its  primary  purpose  of 
protecting  the  oil  industry  and  highly  desirable  in  its  immediate  effect 
of  checking  the  over-development  of  that  day  in  California.  Unfortu- 
nately, however,  through  delays  in  legislation,  this  policy  may  be  regarded 
now  as  having  outlived  both  its  intent  and  its  usefulness.  In  1908,  the 
country's  production  of  oil  was  178,500,000  bbl.,  and  there  was  a  sur- 
plus above  consumption  of  more  than  20,000,000  bbl.  available  to 
go  into  storage.  In  1918,  10  years  later,  the  oil  wells  of  the  United 
States  yielded  356,000,000  bbl. — nearly  twice  the  yield  of  1908— but  to 
meet  the  demands  of  the  increased  consumption  more  than  24,000,000 
bbl.  had  to  be  drawn  from  storage. 

Nor  is  this  all  of  the  brief  comparison.  In  1918,  our  excess  of  imports 
over  exports  of  crude  petroleum  was  nearly  33,000,000  bbl.  whereas  in 
1908  we  exported  3,500,000  bbl.,  which  was  net,  as  we  had  not  begun  to 
import  Mexican  oil.  In  this  period,  the  annual  fuel-oil  consumption 
of  the  railroads  alone  has  increased  from  16,871,000  to  36,714,000  bbl.; 
the  annual  gasoline  production  from  540,000,000  gal.  to  3,500,000,000 
gal.  This  record  may  be  taken  not  only  as  justifying  the  earlier  appeal 
for  Federal  action,  but  as  warranting  deliberate  attention  to  the  oil 
problem  of  today. 

NEED  OF  FUTURE  SUPPLY 

The  position  of  the  United  States  in  regard  to  oil  can  best  be  charac- 
terized as  precarious.  Using  more  than  one-third  of  a  billion  barrels  a 
year,  we  are  drawing  not  only  from  the  underground  pools  but  also  from 
storage,  and  both  of  these  supplies  are  limited.  In  1918,  the  contribu- 

*  Director,  U.  S.  Geol.  Survey. 

1  This  letter,  drafted  by  Dr.  Ralph  Arnold  and  concurred  in  by  Dr.  C.  W.  Hayes 
and  Dr.  D.  T.  Day,  is  quoted  in  Bull  623,  U.  S.  Geol.  Survey,  104. 


90  A   FOREIGN   OIL   SUPPLY   FOR  THE   UNITED   STATES 

tion  direct  from  our  wells  was  356,000,000  bbl.,  or  more  than  one-twen- 
tieth of  the  amount  estimated  by  the  Survey  geologists  as  the  content  of 
our  underground  reserve;  we  also  drew  from  storage  24,000,000  bbl.,  or 
nearly  one-fifth  of  what  remains  above  ground.  Even  if  there  be  no 
further  increase  in  output  due  to  increased  demand,  is  not  this  a  pace 
that  will  kill  the  industry?  Even  though  we  glory  in  the  fact  that  we 
contributed  80  per  cent,  of  the  great  quantity  needed  to  meet  the  require- 
ments of  the  Allies  during  the  war,  is  not  our  world  leadership  more  spec- 
tacular than  safe?  And  even  though  the  United  States  may  today  be 
the  largest  oil  producer  and  though  it  consumes  nearly  75  per  cent,  of 
the  world's  output  of  oil,  it  is  not  a  minute  too  early  to  take  counsel  with 
ourselves  and  call  the  attention  of  the  American  geologists,  engineers, 
capitalists  and  legislators  to  the  need  of  an  oil  supply  for  the  future. 

This  appeal  to  American  brains  and  American  dollars  to  provide  for 
the  future  needs  only  the  backing  of  a  brief  recital  of  the  facts  of  known 
present  needs  and  of  well-justified  expectations  for  the  future.  In  a 
single  decade,  then,  the  consumption  of  fuel  oil  by  railroads  has  more  than 
doubled;  the  consumption  of  gasoline  has  increased  sevenfold.  With 
the  rapidly  mounting  cost  of  coal,  the  competitive  field  of  fuel  oil  for 
steam  use  is  expanding.  But  not  only  is  the  use  of  oil,  both  under 
boilers  and  in  internal-combustion  engines,  thus  increasing,  there  is 
an  even  more  widespread  use  of  a  petroleum  product,  which  was  brought 
to  the  President's  attention  over  10  years  ago.2  Every  new  instal- 
lation of  machinery,  whether  the  60,000-kw.  generator  in  the  Govern- 
ment nitrate  plant  at  Sheffield,  Ala.,  or  the  20-hp.  motor  in  the  small 
automobile,  adds  to  the  country's  demand  for  lubricating  oil,  which  is  an 
essential  in  every  phase  of  modern  civilization.  We  may  lessen  the 
increase  in  coal  or  oil  consumption  for  generating  power  by  harnessing 
the  water  powers  of  the  country;  but  these  prime  movers,  whether 
driven  by  steam  or  water,  require  lubrication.  With  the  rapidly  in- 
creasing use  of  machinery  to  make  labor  more  productive,  with  the 
almost  universal  use  of  the  automobile,  hardly  foreseen  a  decade  ago, 
and  with  the  expected  increase  in  railroad  and  steamship  traffic,  who 
can  venture  an  estimate  of  our  petroleum  requirements,  10  years  hence, 
in  terms  of  lubricatin  oil  alone? 

A  most  serious  aspect  of  our  oil  problem  presents  itself  when  we  con- 
sider the  entry  of  the  United  States  as  a  real  factor  in  the  shipping  of  the 
world — when  we  picture  the  return  of  the  American  flag  to  the  seven 
seas.  Any  nation  which  today  aspires  to  a  large  part  in  world  commerce 
imposes  upon  itself  an  oil  problem,  for  the  future  freedom  of  both  the  sea 
and  the  air  will  be  defined  in  terms  of  oil  supply.  The  new  demand  of 
our  shipping  program  alone  involves  fuel  oil  in  quantities  equivalent 

*  Letter  quoted  in  full  in  Bull.  623,  U.  S.  Geol.  Survey,  134. 


GEORGE    OTIS   SMITH  91 

to  nearly  one-half  of  the  present  domestic  output,  and,  unless  there  is 
some  corresponding  decrease  in  other  demands,  this  new  requirement 
must  be  met  with  an  increase  in  production  of  crude  oil  of  nearly  200,000- 
000  bbl.  How  can  such  quantities  of  oil  be  supplied?  Mr.  Requa's 
earlier  estimate  of  52;COO,000  bbl.  as  the  annual  gain  in  output  needed 
to  meet  the  ordinary  increase  in  consumption  and  to  offset  the  expected 
decline  in  old  wells  would  involve  a  task  laid  upon  our  oil  companies,  in 
their  exploration  and  development  activity,  of  bringing  in  a  million- 
barrel  new  production  each  week.  How  can  the  oil  fields  of  the  United 
States  maintain  such  a  curve  of  new  production? 

Fuel  oil,  gasoline,  lubricating  oil — for  these  three  essentials  are  there 
no  practical  substitutes  or  other  adequate  sources?  The  obvious  answer 
is  in  terms  of  cost;  the  real  answer  is  in  terms  of  man  power.  On  land 
and  on  sea,  fuel  oil  is  preferred  to  coal  because  it  requires  fewer  firemen; 
and  back  of  that,  in  the  man  power  required  in  its  mining,  preparation, 
and  transportation,  the  advantage  on  the  side  of  oil  is  even  greater.  So 
too,  the  substitute  for  gasoline  in  internal-combustion  engines,  whether 
alcohol  or  benzol,  means  higher  cost  and  larger  expenditure  of  labor  in 
its  production.  While  we  have  great  reserves  of  oil  shales  as  an  inde- 
pendent source  of  fuel  oil,  gasoline,  and  lubricating  oil,  it  is  necessary 
to  consider  the  practical  contingency  suggested  by  Mr.  Requa,  that  to 
develop  this  supply  on  a  scale  comparable  in  output  with  our  present  oil 
supply  "would  require  an  industrial  organization  greater  than  our  entire 
coal-mining  organization."  Plainly  our  country  cannot  afford  to  sup- 
port another  such  army  of  workers  until  we  reach  another  stage  in  our 
industrial  development. 

A  country-wide  thrift  campaign  needs  to  be  waged  looking  to  the 
saving  for  this  essential  resource.  Man  power  and  oil  ought  to  be  con- 
served all  along  the  line  of  production  and  consumption  by  better  methods 
in  the  discovery,  drilling,  recovery,  transportation,  refining,  and  use  of 
petroleum  and  its  products.  Unwarranted  optimism,  which  seems 
indigenous  in  most  parts  of  the  United  States,  has  led  both  the  oil  indus- 
try and  the  public  to  waste  this  best  of  fuels;  the  program  of  wastage 
begins  with  leakage  below  ground  and  above  ground  and  continues  to  the 
indiscriminate  burning  of  fuel  oil  under  boilers,  with  regard  for  con- 
venience rather  than  for  efficiency. 

The  estimate  by  the  United  States  Geological  Survey  of  the  oil  re- 
maining in  the  ground  is  of  necessity  subject  to  criticism  as  speculative — 
it  must  contain  errors  in  the  allowances  made  for  isolated  and  undeveloped 
fields — yet  the  excesses  of  unexpected  yield  in  one  region  will  largely  be 
balanced  by  deficiencies  in  another.  Indeed,  as  has  been  suggested  by 
the  Chief  Geologist  of  the  Survey,  if  happily  the  estimate  of  reserve  proves 
too  low,  this  unpredicted  abundance  would  surely  raise  the  consumption 
rate.  On  the  whole,  he  believes  it  fair  to  consider  the  official  estimate  of 


92  A   FOREIGN   OIL   SUPPLY  FOR  THE   UNITED   STATES 

6,500,000,000  bbl.  as  conservative  and  8,000,000,000  as  an  improbable 
maximum.  The  difference  between  these  two  estimates  of  reserves 
represents  only  four  years'  supply,  even  at  the  present  rate  of  consumption. 

It  seems  almost  as  if  divine  providence,  by  the  Gushing  and  Healdton 
"strikes,"  replenished  our  supply  of  oil  "in  storage"  just  in  time  to  enable 
us  to  export  oil  and  gasoline  in  quantities  sufficient  to  justify  Earl  Cur- 
zon's  statement  that  the  "Allied  fleets  floated  to  victory  on  a  sea  of  oil;" 
and  the  Ranger  discovery  was  equally  providential;  yet  the  motto  in- 
scribed on  our  silver  coins  should  hardly  be  made  our  national  policy 
in  providing  a  future  oil  supply. 

It  cannot  be  pointed  out  too  often  that  while  in  the  last  100  years 
the  unprecedented  growth  in  the  industrial  and  transportation  demands 
of  our  country  has  resulted  only  in  the  exhaustion  of  less  than  1  per  cent, 
of  its  coal  resources,  in  the  60  years  since  the  Drake  well  began  our  pro- 
duction apparently  40  per  cent,  of  the  available  oil  has  been  brought  to 
the  surface  and  consumed;  and  the  rate  of  America's  development  is  still 
an  accelerating  rate.  American  interests,  commercial  and  industrial, 
thus  require  a  future  supply  of  crude  oil  outside  the  United  States. 
Indeed,  we  have  been  draining  our  own  oil  pools  in  part  to  supply  the 
needs  of  the  rest  of  the  world,  but  have  made  little  effort  to  render 
the  rest  of  the  world  self-supporting  in  oil  production.  Whether  such  a 
national  policy  is  to  be  characterized  as  that  of  a  spendthrift  or  that 
of  an  altruist,  it  is  a  short-sighted  policy.  With  our  oil  reserves  so 
plainly  inadequate,  it  is  not  too  much  to  treat  our  own  country  under  a 
kind  of  favored-nation  policy.  Surely  the  United  States  can  rightfully 
safeguard  American  interests  at  home  and  abroad,  with  the  spirit  of 
reciprocity  in  trade  relations. 

OBTAINING  A  FUTURE  SUPPLY 

Two  methods  of  handling  the  problem  of  a  future  oil  supply  suggest 
themselves:  either  reserve  the  domestic  oil  fields  for  American  develop- 
ment and  thus  prevent  foreign  acquisition  of  what  is  needed  at  home- 
or,  encourage  our  capital  to  enter  foreign  fields  to  assist  in  their  develop- 
ment, thus  insuring  an  additional  supply  of  oil  for  our  needs.  The 
one  method  harks  back  to  the  "Chinese  wall"  period,  the  other  expresses 
the  "open  door"  policy.  At  present  the  United  States  Government 
follows  neither  method;  the  British  Government  has  adopted  both. 

The  British  Admiralty  led  the  way  in  its  appreciation  of  the  advan- 
tages of  fuel  oil,  and  the  British  Government  has  led  the  way  in  assuring 
to  its  nationals  control  of  oil  resources  wherever  found  on  British  terri- 
tory. Advantages  that  American  capital  may  once  have  held  in  Trinidad 
and  elsewhere  in  the  British  Empire  are  not  now  enjoyed  and  British 
enterprise  is  narrowing  the  field  of  opportunity  in  Mexico,  South  America, 
Mesopotamia,  and  Africa.  Be  it  said,  moreover,  to  the  credit  of  British 


DISCUSSION  93 

efficiency  and  foresight,  that  British  capital  has  made  generous  use  of 
American  brains  in  discovering  and  developing  its  oil  properties.  Ameri- 
can geologists,  American  engineers,  American  drillers,  and  American 
rigs  and  supplies  have  been  utilized  in  British  oil  exploration  and  we  may 
well  reciprocate  by  adopting  the  British  policy  of  encouraging  the  acqui- 
sition by  its  nationals -of  petroleum  supplies  in  foreign  fields.  American 
capital  as  well  as  American  engineering  should  be  encouraged  to  help 
develop  the  new  fields  and  so  do  its  part  in  insuring  the  continuance 
of  this  source  of  power  for  future  generations  at  home  and  abroad. 

The  part  of  the  Government  is  to  give  moral  support  to  every  effort 
of  American  business  to  expand  its  circle  of  activity  in  oil  production  so 
that  it  will  be  coextensive  with  the  new  field  of  American  shipping. 
This  may  mean  world-wide  exploration,  development,  and  producing 
companies,  financed  by  United  States  capital,  guided  by  American 
engineering,  and  safeguarded  in  policy  because  protected  by  the  United 
States  Government. 3  Thus  only  can  our  general  welfare  be  promoted  and 
the  future  supply  of  oil  be  assured  for  the  United  States. 

DISCUSSION 

M.  L.  REQUA,  New  York,  N.  Y.  (written  discussion). — This  paper 
calls  attention  to  what  is  perhaps  our  most  critical  raw-material  problem. 
I  have  spoken  and  written  so  vigorously  and  frequently  upon  this  sub- 
ject that  it  seems  almost  useless  repetition  to  refer  again  to  the  subject; 
but,  in  the  face  of  everything  that  has  been  said  and  done  by  various 
individuals  alive  to  the  situation,  we  are  utterly  without  any  national 
policy  as  related  to  foreign  sources  of  petroleum  supply.  We  build  up 
a  great  mercantile  marine  and  predicate  its  success  upon  fuel  oil,  but 
we  make  no  really  constructive  effort  to  assure  the  source  of  supply  for 
that  material.  We  construct  warships  made  to  burn  nothing  but  fuel 
oil,  and  we  face  a  lack  of  preparedness  and  appreciation  of  the  gravity  of 
the  situation  on  the  part  of  the  directing  head  of  the  Navy  that  would 
be  grotesque  were  it  not  for  the  tragedy  involved. 

3  In  his  annual  report  to  the  President,  the  Secretary  of  the  Interior  states  (pp. 
18-20)  that  the  present  situation  "calls  for  a  policy  prompt,  determined,  and  look- 
ing many  years  ahead."  The  supplemental  supply  needed  "may  be  secured,"  he 
says,  "  through  American  enterprise  if  we  do  these  things:  (1)  Assure  American 
capital  that  if  it  goes  into  a  foreign  country  and  secures  the  right  to  drill  for  oil  on 
a  legal  and  fair  basis  (all  of  which  must  be  shown  to  the  State  Department)  that 
it  will  be  protected  against  confiscation  or  discrimination.  This  should  be  a  known 
published  policy.  (2)  Require  every  American  corporation  producing  oil  in  a  foreign 
country  to  take  out  a  Federal  charter  for  such  enterprise  under  which  whatever  oil 
it  produces  should  be  subject  to  a  preferential  right  on  the  part  of  this  Government 
to  take  all  of  its  supply  or  a  percentage  thereof  at  any  time  on  payment  of  the 
market  price.  (3)  Sell  no  oil  to  a  vessel  carrying  a  charter  from  any  foreign  govern- 
ment either  at  an  American  port  or  at  any  American  bunker  when  that  government 
does  not  sell  oil  at  a  non-discriminatory  price  to  our  vessels  at  its  bunkers  or  ports." 


94  A   FOREIGN   OIL   SUPPLY  FOR   THE   UNITED   STATES 

The  day  of  reckoning  must  come,  of  course,  in  all  things;  and  our 
Government  officials  have  before  them  a  very  unpleasant  experience 
when  they  have  to  explain  the  lack  of  foresight  as  regards  petroleum. 
The  documents  on  file  in  various  governmental  departments  in  Washing- 
ton calling  attention  to  this  situation  would  make,  if  assembled  as  a 
whole,  extremely  interesting  reading — in  the  light  of  events.  To  my 
knowledge,  the  Director  of  the  Geological  Survey  has  for  at  least  five 
years  been  urging  proper  consideration  of  the  subject. 

CHESTER  W.  WASHBURNE,  New  York,  N.  Y.  (written  discussion).— 
It  is  a  delightful  surprise  to  read  Doctor  Smith's  statement  that  the  policy 
of  withdrawing  government  oil  lands  ' '  may  be  regarded  now  as  having 
outlived  both  its  intent  and  its  usefulness."  It  has  indeed  become  a 
nuisance  and  an  injustice  to  anyone  who  discovers  oil  on  the  public 
domain,  only  to  have  the  benefits  of  his  intelligence  and  daring  snatched 
away  by  Presidential  decree.  Everyone,  even  the  old-timers  who 
thought  differently,  now  recognize  that  the  oil  supplies  of  this  country  are 
wholly  inadequate  for  our  own  future  needs.  The  passage  of  a  good  leas- 
ing bill  will  help  a  little;  the  development  of  foreign  oil  fields  is  the  great 
necessity. 

Foreign  development  of  any  consequence  requires  two  things.  First, 
there  should  be  greater  backbone  in  the  American  State  Department  and 
President  in  protecting  and  helping  American  capital  in  foreign  fields. 
The  recommendations  of  the  Secretary  of  the  Interior  outlined  by  Doctor 
Smith  would  help,  if  adopted.  Secondly,  there  should  be  greater  and 
more  persistent  efforts  of  American  capital  in  hazardous  foreign  under- 
takings. The  second  element  already  shows  manifestations  of  serious 
importance.  In  the  first  we  are  outclassed  by  the  well-knit  organiza- 
tion of  the  British  Foreign  Office  and  the  harmoniously  working  British 
Consular  Service. 

In  view  of  the  great  risks  involved  and  the  high  expenditures,  it 
would  be  wise  for  American  companies  to  combine  in  some  way  for  foreign 
work.  The  principal  American  companies  working  in  any  one  foreign 
country  should  be  able  to  pool  their  interests  in  some  way,  to  avoid 
bidding  against  each  other  for  concessions,  etc.  One  way  in  which  this 
could  be  done  is  exemplified  by  the  British  companies  in  Venezuela, 
which  operate  independently  in  the  field,  each  in  its  own  area,  but  which 
are  in  close,  though  more  or  less  secret,  association  in  London.  They 
practically  have  cornered  the  best  part  of  Venezuela,  while  the  American 
companies  remained  uninterested.  We  soon  will  regret  this  oversight. 
As  an  example  of  the  way  American  companies  work,  I  will  cite  one 
experience.  Several  years  ago,  I  had  a  distinguished  oil  geologist  examine 
certain  properties  in  Colombia.  He  condemned  them.  Since  then  four 
American  companies  successively  have  sent  expeditions  to  examine  the 


DISCUSSION  95 

same  properties,  and  since  no  one  has  taken  them  I  presume  all  geologists 
have  condemned  them.  The  mouth  of  each  geologist  is  sealed  by  pro- 
fessional ethics,  but  the  heads  of  the  companies  in  question  might  have 
been  friendly  enough  to  prevent  this  foolish  reduplication.  I  believe 
these  properties  will  remain  on  the  market  for  future  examination,  until 
some  company  happens  to  send  a  poor  geologist  who  will  allow  his 
employers  to  pay  a  big  bonus  and  drill  some  dry  holes.  Meanwhile 
British  capital  has  been  strengthening  its  position  in  the  more  desirable 
territory  to  the  east,  Venezuela. 

Two  American  companies  have  been  trying  to  get  another  Colombian 
property  that  looks  rather  attractive,  but  their  efforts  have  resulted 
in  boosting  the  price  to  a  foolish  figure.  Development  is  delayed  until 
the  owners  will  listen  to  reason.  Cooperation  would  have  saved  this 
situation.  Cooperation  would  have  resulted  in  definite  development 
in  other  foreign  affairs  where  Americans  have  been  competing  with  each 
other. 

R.  H.  JOHNSTON,*  Washington,  D.  C. — The  remarks  just  made 
emphasize  the  fact  that  Great  Britain  enjoys  a  much  more  vigorous 
foreign  policy  than  does  this  country.  During  the  discussion  regarding 
the  Persian  oil  fields,4  the  suggestion  was  made  that  American  companies 
should  take  part  in  the  development  of  these  fields.  On  Aug.  9,  1919, 
Great  Britain  signed  a  treaty  with  Persia,  from  which  I  will  read  three 
paragraphs: 

(2)  The  British  Government  will  supply,  at  the  cost  of  the  Persian  Government, 
the  services  of  whatever  expert  advisers  may,  after  consultation  between  the  two 
governments,  be  considered  necessary  for  the  several  departments  of  the  Persian 
administration.     These  advisers  shall  be  engaged  on  contracts  and  endowed  with 
adequate  powers,  the  nature  of  which  shall  be  the  matter  of  agreement  between  the 
Persian  Government  and  the  advisers. 

(3)  The  British  Government  will  supply,  at  the  cost  of  the  Persian  Government, 
such  officers  and  such  munitions  and  equipment  of  modern  type  as  may  be  adjudged 
necessary  by  a  joint  commission  of  military  experts,  British  and  Persian,    which 
shall  assemble  forthwith  for  the  purpose  of  estimating  the  needs  of  Persia  in  respect 
of  the  formation  of  a  uniform  force  which  the  Persian  Government  proposes  to 
create  for  the  establishment  and  preservation  of  order  in  the  country  and  on  its 
frontiers. 

(4)  For  the  purpose  of  financing  the  reforms  indicated  in  clauses  two  and  three 
of  this  agreement,  the  British  Government  offers  to  provide  or  arrange  a  substantial 
loan  for  the  Persian  Government,  for  which  adequate  security  shall  be  sought  by  the 
two  governments  in  consultation  in  the  revenues  of  the  customs  or  other  sources  of 
income   at   the  disposal  of  the  Persian  Government.     Pending  the  completion  of 
negotiations  for  such  a  loan,  the  British  Government  will  supply  on  account  of  it 
such  funds  as  may  be  necessary  for  initiating  the  said  reforms. 

*  Vice  President,  The  White  Co.  4  See  p.  16. 


96  A   FOREIGN   OIL  SUPPLY  FOE  THE   UNITED   STATES 

So  you  see  that  the  Persian  oil  fields  are  pretty  well  controlled  by 
Great  Britain.  Not  only  is  Great  Britain  pursuing  its  historic  policy 
of  making  the  lives  and  investments  of  British  subjects  safe  in  every 
part  of  the  world,  but  this  treaty  practically  puts  the  administration  of 
Persia's  affairs  into  the  hands  of  British  advisers.  It  would  not  be 
desirable  for  the  United  States  to  make  treaties  of  this  kind,  but  the  suc- 
cessful development  of  foreign  fields  by  American  capital  hinges  entirely 
upon  our  having  a  vigorous  foreign  policy. 


PETROLEUM  RESOURCES  OF  KANSAS  97 


Petroleum  Resources  of  Kansas 

BY  RAYMOND  C.  MOORE,*  PH.  D.,  LAWRENCE,  KANS. 

(New  York  Meeting,  February,  1920) 

THE  oil-producing  districts  of  Kansas  comprise  the  northern  portion 
of  the  so-called  Mid-Continent  field.  As  shown  in  the  accompanying 
map,  these  districts  are  located  chiefly  in  the  southeastern  and  south 
central  parts  of  the  state.  A  considerable  area  in  southeastern  Kansas, 
extending  northward  nearly  to  Kansas  City,  has  long  been  known  as  oil 
territory,  the  productive  wells  being  distributed  in  patches  or  spots  of 
irregular  size  and  shape,  the  location  of  which  is  controlled  by  conditions 
of  rock  structure,  and  by  the  texture  and  porosity  of  the  "sands"  beneath 
the  surface.  In  south  central  Kansas,  there  are  a  number  of  producing 
fields,  the  location  of  which  appears  to  be  controlled  chiefly  by  well-de- 
fined structure.  The  most  important  districts  are  those  in  Butler  County, 
especially  that  in  the  vicinity  of  El  Dorado,  which  was  for  a  time  the  most 
productive  district  in  the  entire  Mid-Continent  field.  Recently  new  pro- 
duction of  importance  has  been  brought  in  the  vicinity  of  Peabody  and 
present  development  is  active  to  the  north  across  Marion  County.  Tests 
in  the  western  parts  of  Kansas  have  not  been  successful  in  finding  new 
petroleum  fields. 

HISTORY 

The  first  well  drilled  for  petroleum,  in  Kansas,  was  near  the  town  of 
Paola,  Miami  Co.,  about  40  mi.  southwest  of  Kansas  City,  in  the  summer 
of  1860,  only  a  few  months  after  the  completion  of  the  famous  "Colonel" 
Drake  discovery  well  in  Pennsylvania.  Kansas  appears  to  be  the  second 
state  to  engage  in  a  serious  attempt  to  find  oil  by  drilling.  The  Civil 
War  caused  the  temporary  abandonment  of  attempts  at  oil  development 
in  the  state. 

It  was  in  the  vicinity  of  Paola,  where  numerous  oil  seepages  had  been 
observed,  that  the  first  well  producing  oil  in  commercial  quantities  was 
drilled,1  where  also  gas  was  first  piped  to  the  city  for  commercial  use. 
Prospecting  spread  southward  into  Linn  County  and  northward  into 

*  State  Geologist  of  Kansas. 

1  Raymond  C.  Moore  and  Winthrop  P.  Haynes :  Oil  and  Gas  Resources  of  Kansas. 
Kans.  Geol.  Survey  Bull  3a  (1917)  20. 
voi,.  ijcv. — 7 


98 


PETROLEUM  RESOURCES  OF  KANSAS 


Johnson  and  Wyandotte  Counties,  a  number  of  small  gas  wells  being  ob- 
tained. Later  development  extended  southward  toward  lola,  Chanute, 
Neodesha  and  Coffeyville,  reaching  to  the  boundary  of  the  Indian  Terri- 


Ixxjation  Map  of 
-CONTrNENT  FIELD 

AFTER   DAVIO  T.  DAY 

Scale  1:  5,OOO.OOO 


FlG.    1. 


tory,  now  Oklahoma.  From  1891  until  1894,  prospectors  covered  the 
entire  southeastern  part  of  Kansas  along  the  Neosho  and  Verdigris  rivers. 
Many  oil  wells,  though  none  with  very  large  individual  production,  were 


RAYMOND    C.    MOORE  99 

brought  in,  particularly  in  Allen,  Neosho,  Montgomery,  and  Wilson 
Counties. 

The  production  of  petroleum  in  Kansas  amounted  to  relatively  little 
until  tests  completed  in  the  then  Indian  Territory  showed  that  beneath  the 
Mid-Continent  plains  lay  really  important  deposits  of  oil.  The  great 
impetus  then  given  to  drilling  in  Kansas  resulted  in  a  very  rapid  increase 
in  the  volume  of  production.  Although  in  1900  less  than  75,000  bbl.  of 
oil  were  obtained  in  the  entire  state,  the  production  in  1904  amounted  to 
4,250,779  bbl.  Due  to  the  decline  in  price,  drilling  fell  off  and  so  large 
an  annual  production  was  not  again  reached  until  1916  when,  with  a 
considerably  increased  market  price  and  the  recent  discovery  of  the  rich 
Butler  County  fields,  the  production  of  the  state  was  brought  to  nearly 
9,000,000  barrels. 

The  larger  place  which  Kansas  has  occupied  in  recent  years  as  a  pro- 
ducer of  petroleum  is  almost  wholly  due  to  the  discovery  in  June,  1914, 
of  commercial  quantities  of  oil  in  Butler  County,  south  central  Kansas. 
It  has  been  known  for  a  number  of  years  that  gas  was  available  in  this 
part  of  the  state.  One  of  the  wells  in  the  Augusta  gas  district  was  drilled 
into  an  oil  sand  at  a  depth  of  about  2500  ft.  (761  m.)  and  before  the  end  of 

1914  five  oil  wells  had  been  drilled  in  the  heart  of  the  gas  field.    By  the 
close  of  1915,  the  number  of  oil  wells  was  increased  to  twelve,  one  of 
which  is  reported  to  have  had  an  initial  natural  flow  of  1500  bbl.     Mean- 
while, geological  examination  of  the  country  to  the  north  revealed  a  very 
promising  structure  in  the  vicinity  of  El  Dorado.     In  the  latter  part  of 

1915  the  Continental  Oil  &  Gas  Co.,  now  the  Empire  Gas  &  Fuel  Co., 
brought  in  a  100-bbl.  well  on  the  Stapleton  farm,  section  29,  township  25 
south,  range  5  east,  about  15  mi.  northwest  of  Augusta.      The  discovery 
was  in  a  sand  penetrated  at  a  depth  of  about  660  ft.  (198  m.)     Offset  wells 
confirmed  the  importance  of  the  shallow  sand  but  in  the  first  well  the  sand 
was  cased  off  and  the  drilling  continued.     A  lower  productive  sand  was 
encountered  at  a  reported  depth  of  2460  ft.,  the  well  being  completed  with 
an  initial  production  of  120  bbl.  a  day  from  this  horizon.     Succeeding 
wells  were,  for  a  time,  drilled  into  the  shallow  sand  only.    Later  the 
deeper  sands  were  developed,  culminating  in  the  disco  very  and  exploitation 
of  the  2500-ft.  sand  in  the  Towanda  district  in  the  spring  and  summer  of 
1917,     Some  of  the  wells  in  this  district  are  reported  to  have  had  an 
initial  daily  production  of  more  than  25,000  barrels. 

In  the  latter  part  of  1918,  oil  was  discovered  in  the  extreme  north- 
western part  of  Butler  County  east  of  Elbing.  The  wells  were  not  im- 
portant, but  the  drilling  in  the  early  part  of  1919  on  a  favorable  structure 
south  of  Peabody,  Marion  Co.,  was  marked  by  large  production.  The 
present  activity  in  development  is  in  this  region  and  northward  across 
Marion  County  into  Dickinson  County. 


100  PETROLEUM  RESOURCES  OF  KANSAS 

STRATIGRAPHY 

In  general,  the  geology  of  Kansas  is  almost  ideally  simple.  The  state  is 
a  typical  part  of  the  Great  Plains  region  and  has  the  uniformly  gentle  slope 
and  simplicity  of  geologic  structure  which  characterize  the  plains.  The 
surface  of  Kansas  has  a  general  inclination  from  west  to  east  amounting 
to  about  10  ft.  (3  m.)  per  mile,  the  elevation  of  the  western  state  boundary 
being  about  3500  to  4000  ft.,  that  of  the  eastern  boundary  from  750  to 
1000  ft.  The  rock  formations  of  which  this  sloping  plain  is  built  lie 
almost  flat  and  are  exposed  in  broad  north-and-south  bands  across 
the  state.  They  sag  slightly  in  central  Kansas,  the  rock  slope,  or 
dip,  being  toward  the  west  in  the  eastern  counties  and  to  the  east  in  the 
western  part  of  the  state.  The  oldest  beds  appear  at  the  surface  in  the 
east  and  dip  beneath  the  younger  overlying  formations,  which  appear  in 
succession  as  the  state  is  crossed  to  the  west. 

The  rocks  in  the  general  region  of  the  Mid-Continent  field  range  in 
geologic  age  from  almost  the  oldest  known  to  the  youngest.  The  oldest 
rocks  are  granites  and  other  crystalline  rocks  of  pre-Cambrian  age,  which 
are  exposed  in  the  southeastern  part  of  Missouri,  in  the  Ar buckle  and 
Wichita  Mountains  of  Oklahoma,  in  the  Rocky  Mountains  of  Colorado, 
and  at  points  north  of  Kansas  farther  distant.  The  pre-Cambrian  no- 
where appears  at  the  surface  in  Kansas,  but  recent  exploration  for  oil 
and  gas  in  the  central  part  of  the  state  suggests  that  it  approaches 
the  surface  much  more  closely  than  was  supposed.  Sufficient  tests  have 
been  made  to  indicate  quite  clearly  the  presence  of  a  buried  ridge  or 
mountain  range  of  granite,  which  appears  to  trend  in  a  direction  slightly 
east  of  north  from  Butler  County  to  the  northern  limits  of  the  state. 
No  evidence  of  metamorphism  of  the  sedimentary  rocks  immediately 
overlying  the  granite  has  been  found,  and  it  is  probable  that  the  ridge 
represents  a  part  of  the  pre-Cambrian  floor. 

Table  1  presents  the  chief  stratigraphic  divisions  of  the  rocks  of 
Kansas. 

Strata  which  belong  to  the  Cambrian  and  Ordovician,  consisting  of 
dolomites,  limestones,  shales,  and  sandstones,  and  aggregating  about 
2000  ft.  (609  m.)  in  thickness,  underlie  eastern  Kansas  and  perhaps  other 
parts  of  the  state.  They  have  been  penetrated  in  a  number  of  wells  but 
in  no  place  found  to  contain  commercial  quantities  of  petroleum  or  natural 
gas.  Upon  the  eroded  surface  of  the  rocks  of  the  older  Paleozoic,  in  the 
Great  Plains  country,  is  found  the  Mississippian  system,  or,  as  it  is  called 
by  drillers,  the  "Mississippi  lime."  The  Mississippian  is  a  clearly 
defined,  readily  traceable,  stratigraphic  unit,  consisting  chiefly  of 
crystalline  limestones  containing  a  rather  unusual  amount  of  hard 
flinty  chert. 


RAYMOND   C.   MOORE 

TABLE  1. — Geologic  Section  of  the  Kansas  Region 


101 


System 

Groups 

Formation 

Character  of  Rocks 

Cenozoic 

Quaternary 

Recent 

Alluvium,  dune  sands 

Pleistocene 

Wisconsin  stage 
Kansas  stage 

Glacial  deposits 

Tertiary 

Pliocene 
Miocene 

Ogalalla 

Gravel,  sand,  clay 

Mesozoic 

Cretaceous 

Montana 

Pierre 

Shale 

Colorado 

Niobrara 
Benton 

Limestone,  chalk,  shale 

Dakota 

sandstone 

Sandstone,  shale 

Comanchean 

Washita 

Kiowa 
Cheyenne 

Sandstone,  shale 

Ins 
Not  exposed  in  Kansas  £, 
2 

zoic 

Permian 

Cimarron 

Greer 
Woodward 
Cave  Creek 
Enid 

"Red  beds,"  sandstone, 
shale,    dolomite,    gyp- 
sum, salt 

Big  Blue 

Wellington 
Marion 
Chase 
Council  Grove 

Shale,  limestone 

Pennsylvanian 

Missouri 

Wabaunsee 
Shawnee 
Douglas 
Lansing 
Kansas  City 

Limestone,  shale,   sand- 
stone 

Des  Moines 

Marmaton 
Cherokee 

Limestone,  shale,   sand- 
stone 

Mississippian 

Unconformity    — 
Ordovician 

Chester 
Unconformity 

Osage 

Warsaw 
Keokuk 
Burlington 
Pierson 

Limestone 

Pre-Cambrian 

Kinderhook 

Limestone,  shale 

Joachim 
Jefferson  City 
Roubidoux 

Dolomite,  sandstone, 
shale 

Cambrian 

Gasconade 
Proctor 
Eminence 
Potosi 

102  PETROLEUM  RESOURCES  OF  KANSAS 

TABLE  2. — Divisions  of  Pennsylvanian  Rocks  of  Kansas 


Group 

Formation 

Member 

Thickness, 
Feet 

Eskridge  shale 

30-40 

Neva  limestone 

3-5 

Elm  dale  shale 

120-140 

Wabaunsee  formation 

Americus  limestone 

6-10 

Admire  shale1 

276-325 

Emporia  limestone 

5-10 

Willard  shale 

45-55 

Burlingame  limestone 

7-12 

Scranton  shale 

160-200 

Howard  limestone 

3-7 

Severy  shale 

40-60 

Topeka  limestone 

20-25 

Shawnee  formation 

Calhoun  shale 

0-50 

Deer  Creek  limestone 

20-30 

Tecumseh  shale 

40-70 

Lecompton  limestone 

15-30 

Kanwaka  shale 

50-100 

Missouri 

Oread  limestone 

50-70 

Lawrence  shale* 

150-300 

Douglas  formation 

latan  limestone 

3-15 

Weston  shale 

60-100 

Stanton  limestone 

20-40 

Vilas  shale 

5-125 

Lansing  formation 

Plattsburg  limestone 

5-80 

Lane  shale 

50-150 

lola  limestone 

2-40 

Chanute  shale 

25-100 

Drum  limestone 

0-80 

Cherryvale  shale* 

25-125 

Kansas  City  formation 

Winterset  limestone 

30-40 

Galesburg  shale 

10-60 

Bethany  Falls  limestone 

4-25 

Ladore  shale 

3-50 

Hertha  lime&tone 

10-20 

Pleasanton  shale 

100-150 

Coffeyville  limestone 

8-10 

shale 

60-80 

Marmaton  formation 

Altamont  limestone 

3-10 

Des  Moines 

Bandera  shale 

60-120 

Pawnee  limestone 

40-50 

Labette  shale 

0-60 

Fort  Scott  limestone 

20-40 

Cherokee  shale4 

Undifferentiated 

400-500 

1  Possibly  contains  shallow  oil  sand  at  El  Dorado. 

*  Includes  Chautauqua  sandstone  member;  probably  1500-ft.  sand  at  Augusta  and  El  Dorado. 

*  Possibly  horizon  of  oil  sand  at  2400  ft.  at  Augusta  and  El  Dorado. 

*  Includes  the  main  oil  sand  outside  Augusta  and  El  Dorado  and  Peru;  contains  Bartlesville  and 
Burgess  sands. 


RAYMOND    C.    MOORE  103 

In  Oklahoma  and  northern  Arkansas,  it  includes  important  beds  of  shale 
and  some  sandstone;  but  where  encountered  by  the  drill  in  Kansas  and 
throughout  most  of  Missouri,  it  is  essentially  a  limestone  series.  An 
exception,  apparently,  is  found  in  central  Kansas,  according  to  recent  in- 
formation from  well  records,  which  indicate  a  disappearance  locally  of 
the  limestone  and  a  replacement  by  clastic  material.  The  thickness  of 
the  system  in  the  south  central  part  of  the  Mississippi  basin  is  more  than 
2000  ft.,  but  in  Kansas  it  is  not  more  than  300  or  350  ft. 

The  oil  and  gas  deposits  of  the  Mid-Continent  field  are  confined  almost 
wholly  to  rocks  of  the  Pennsylvanian  system,  which  outcrop  in  a  broad 
belt  across  eastern  Kansas  and  Oklahoma.  The  rocks  of  this  system 
consist  of  a  thick  series  of  alternating  shale  and  limestone  formations, 
with  irregular  beds  of  sandstone  and  some  beds  of  coal.  Though  not 
great  in  thickness,  many  of  the  beds  are  surprisingly  persistent  hori- 
zontally, having  been  traced  in  most  cases  some  hundreds  of  miles  along 
the  outcrop.  They  have  a  total  thickness  of  nearly  3500  ft.  in  the  south- 
ern part  of  the  state  and  a  slightly  smaller  amount  to  the  north.  A  total 
thickness  of  about  3000  ft.  has  been  measured  along  Kansas  River. 

Table  2  shows  the  stratigraphic  divisions  of  the  Pennsylvanian  that 
have  been  recognized  in  Kansas,  with  their  approximate  thicknesses. 

Permian  rocks  are  found  in  a  north-  and-  south  band  across  central 
Kansas.  The  zone  of  outcrop  is  narrow  at  the  north,  where  it  is  over- 
lapped from  the  west  by  the  much  younger  beds  of  Cretaceous  age,  and 
reaches  its  maximum  width  near  the  southern  border  of  the  state.  The 
lower  Permian  beds  are  marine  and  overlie  the  upper  Pennsylvanian  strata 
without  unconformity  or  other  prominent  mark  of  stratigraphic  division. 
The  upper  Permian,  which  is  confined  to  the  southwestern  part  of  the 
Permian  area  in  the  state,  consists  chiefly  of  red  beds.  The  subdivisions 
which  have  been  made  are  listed  in  Table  3,  with  approximate  thickness. 

The  remainder  of  the  surface  in  Kansas  is  occupied  by  rocks  of  Cre- 
taceous and  Tertiary  age.  The  former  consists  of  an  important  basal 
division  of  sandstone,  the  Dakota,  and  of  middle  and  upper  divisions  of 
chalky  limestone  and  shale.  The  total  thickness  is  approximately  1300 
ft.  Seepages  of  oil  have  been  reported  in  the  Cretaceous  area  and  there 
are  some  excellent  structures,  but  no  commercial  production  of  oil  has 
been  obtained  from  these  rocks  or  in  the  part  of  the  state  in  which  they 
outcrop. 

In  common  with  the  Mississippian  and  older  systems  that  underlie  it, 
the  Pennsylvanian  strata  have  a  gentle  inclination  outward  from  the 
Ozark  highland.  In  northeastern  Kansas,  they  dip  toward  the  north- 
west; in  central  eastern  Kansas,  almost  due  west;  and  in  the  southern 
counties,  slightly  southwest.  If  the  Pennsylvanian  is  continuous  be- 
neath the  thick  overlying  formations  of  Permian,  Cretaceous,  and  Ter- 
tiary age  in  the  western  part  of  Kansas,  the  system  is  a  part  of  the  broad 


104  PETBOLEUM  RESOURCES  OF  KANSAS 

TABLE  3. — Subdivisions  of  Permian  System  in  Kansas 


Group 

Formation 

Member 

Thickness, 
Feet 

Greer 

Big  Basin  sandstone 

12 

shale 

20 

Day  Creek  dolomite 

1-5 

Woodward 

Whitehorse  sandstone 

175-200 

Dog  Creek  shale 

30 

Cimmaron 

Shimer  gypsum 

4-25 

Cave  Creek 

Jenkins  shale 

5-50 

Medicine  Lodge  gypsum 

2-30 

Flowerpot  shale 

150 

Enid 

Cedar  Hills  sandstone 

50-60 

Salt  Plain  shale 

155 

Harper  sandstone 

350 

Wellington 

Undifferentiated 

500-800 

Abilene  limestone 

4-8 

Pearl  shale 

70 

Marion 

Herington  limestone 

12-15 

Enterprise  shale 

35^4 

Luta  limestone 

30 

Big  Blue 

Winfield  limestone 

20-25 

Doyle  shale 

60 

Chase 

Fort  Riley  limestone 

40-45 

Florence  flint 

20 

Matfield  shale 

60-70 

Wreford  limestone 

35-50 

Council  Grove 

Garrison  shale  and  limestone 

135-150 

Cottonwood  limestone 

6 

shallow  sag,  or  syncline,  that  characterizes  the  general  structure  of  the 
state.  However,  when  examined  in  detail  it  is  seen  that  there  are  many 
irregularities  in^the  structure  of  the  Pennsylvanian  rocks.  In  many 
places  in  eastern  Kansas,  the  rock  strata  are  absolutely  horizontal, 
and  in  a  number  of  places,  they  are  inclined  to  the  east  for  short  dis- 
tances. These  irregularities  are  minor  waves  on  the  major  structure 
of  the  Pennsylvanian  but  are,  in  most  instances,  the  controlling  feature 
in  the  accumulation  of  commercial  deposits  of  oil.  Most  of  the  minor 
structures  are  of  the  unsymmetrical  dome  type,  the  rocks  dipping  away 
in  all  directions.  Others  are  merely  terraces,  or  "noses, "  where  the 
western  dip  is  diminished  sufficiently  to  permit  local  accumulation  of 
petroleum.  None  of  the  structures  are  very  prominent,  the  vertical 


RAYMOND    C.    MOORE 


105 


distance  from  the  top  of  one  of  the  best  defined  anticlines  to  the  upper 
part  of  the  adjacent  saddle,  that  is  the  closure,  being  only  160  feet. 

The  texture  of  the  "sand"  is  a  controlling  factor  in  the  production 
of  areas  in  southeastern  Kansas.  Oil  and  gas  wells  with  an  important 
production  are  located  in  many  instances  without  relation  to  structure, 
the  supply  of  oil  and  gas  being  controlled  by  the  lenticular  character 
or  the  "patchy"  texture  of  the  sands. 

TECHNOLOGY 

Two  types  of  drilling  are  employed  in  the  Kansas  fields,  the  standard, 
or  cable  drilling,  which  is  used  in  all  the  deeper  wells,  and  the  Star,  or 
Parkersburg  type,  which  is  commonly  used  in  the  shallow  fields  of  the 
eastern  part  of  the  state. 

On  account  of  water  conditions  in  certain  parts  of  the  Kansas  fields, 
especially  in  the  El  Dorado  and  Augusta  districts,  the  depth  to  which  the 
oil-producing  sand  is  penetrated  and  the  casing  of  the  well  are  important 
considerations.  If  the  well  is  drilled  too  deep,  there  is  danger  of  drowning 
within  a  comparatively  short  time.  In  most  cases,  only  the  ordinary 
requirements  of  casing  are  met.  The  use  of  cement  and  the  mud- 
laden  fluid  has  been  successful,  where  employed  in  the  Butler  County 
wells,  but  there  has  been  no  uniformity  of  practice,  due  to  varying  condi- 
tions in  the  field  and  to  lack  of  state  supervision. 

PRODUCTION  STATISTICS 

Most  of  the  wells  in  the  Kansas  fields  are  not  large  producers,  the 
average  yield  amounting  to  but  a  few  barrels  a  day.  The  largest  pro- 
duction from  individual  wells  has  been  found  in  the  El  Dorado-Towanda 
district,  where  at  least  one  well  is  reported  to  have  flowed  more  than 
25,000  bbl.  a  day.  The  initial  production  of  many  wells  in  this  part  of 
the  state  has  exceeded  2000  bbl.  a  day.  Table  4  shows  the  average  pro- 
duction of  oil  wells  in  Kansas  from  1910  to  1918  based  on  available  data. 

TABLE  4. — Average  Production  of  Oil  Wells  in  Kansas,  1910-1918 


Year 

Total  Produc- 
tion, Barrels 

Total  Number, 
Oil  Wells 

Dry  Holes 

Average  Annual 
Production  per 
Well,  Barrels 

Average  Daily 
Production  per 
Well,  Barrels 

1910 

1,128,668 

1,831 

25 

616 

1.7 

1911 

1,278,819 

1,787 

25 

715 

1.9 

1912 

1,592,796 

1,757 

41 

906 

2.5 

1913 

2,375,029 

1,812 

87 

1,310 

3.5 

1914 

3,103,585 

3,054 

156 

1,016 

2.8 

1915 

2,823,487 

3,460 

158 

810 

2.2 

1916 

8,738,077 

3,673 

360 

2,379 

6.5 

1917 

36,536,125 

5,843 

420 

6,253 

17.1 

1918 

43,253,470 

8,950 

925 

4,833 

13.2 

106  PETROLEUM  RESOURCES  OF  KANSAS 

The  crude  petroleum  has  a  specific  gravity  ranging  from  about  20° 
Baume*,  for  some  of  the  southeastern  oils,  to  40°  or  slightly  higher  for 
some  of  the  oils  in  the  Butler  County  district.  The  specific  gravity  of  the 
oil  in  the  vicinity  of  Chanute,  Coffeyville,  and  Independence  is  about 
30°  to  32°.  This  heavy  oil  has  considerably  less  gasoline  than  the  oils 
with  higher  specific  gravity.  On  account  of  this  there  has  been  a  tendency 
for  some  of  the  refineries  to  move  to  points  from  which  a  larger  supply  of 
higher  grade  oil  could  readily  be  obtained. 

The  oil  is  gathered  by  pipe  lines  from  the  producing  fields  in  the  Butler 
County  district  and  from  other  important  areas,  pipe  lines  converging 
toward  the  northeast  in  the  vicinity  of  Kansas  City.  A  considerable 
number  of  tank  cars  are  used  both  in  the  transportation  of  crude  oil 
from  some  of  the  fields  and  in  the  distribution  of  the  refined  product. 

According  to  the  best  available  records,  Kansas  had  produced  to  the 
end  of  the  year  1918  a  grand  total  of  119,898,233  bbl.  of  crude  oil.  The 
character  of  the  Kansas  oil  fields  is  in  part  indicated  by  the  statistics  of 
wells  drilled.  Throughout  the  larger  part  of  the  producing  area,  especially 
that  located  in  the  southeastern  counties  of  the  state,  the  wells  are  num- 
erous, but  none  have  a  large  output.  The  average  yield  for  each  producing 
well  is  from  1  or  2  to  25  bbl.  a  day.  In  the  Butler  County  fields,  some  of 
the  wells  were  credited  with  a  very  large  individual  daily  output.  In 
general,  the  interest  in  development  and  activity  in  the  fields  is  also  shown 
by  the  number  of  new  wells  drilled.  Field  operations  follow  more  or 
less  closely  the  fluctuation  of  the  market,  periods  of  greatest  activity  ac- 
companying times  of  highest  crude-oil  prices.  In  the  years  1912  to  1918, 
inclusive,  13.649  wells  were  drilled,  of  which  10,979  were  producing  and 
2670  dry.  Of  the  4671  wells  put  down  in  1918,  2549  were  oil  producing 
and  272  gas  wells. 

FUTURE  POSSIBILITIES 

At  the  present  writing,  the  rich  Butler  County  fields  are  past  the 
zenith  of  their  production,  the  climax  having  been  reached  with  the  de- 
velopment of  the  Towanda  district,  which  reached  its  peak  in  1918. 
The  discovery  of  new  fields,  east  of  Elbing  and  extending  toward  Peabody, 
in  Marion  County,  has  given  new  impetus  to  development  in  this  part 
of  the  state.  Tests  south  of  the  El  Dorado  and  Augusta  fields,  toward 
the  Blackwell  area,  have  thus  far  given  little  encouragement,  but  satis- 
factory showings  in  structures  located  in  Marion  County  and  northward 
into  Dickinson  County  are  attracting  considerable  attention. 

Southeastern  Kansas  fields  have  been  thoroughly  tested  and,  with  the 
exception  of  new  wells  in  porous  sands  that  have  not  yet  been  drained, 
there  is  little  additional  production  to  be  expected.  It  is  possible  that 
new  pools  will  be  discovered  in  part  of  the  state  between  the  old  oil  and 


RAYMOND    C.    MOORE  107 

gas  fields  in  the  vicinity  of  Chanute,  lola,  and  Independence,  and  the 
fields  farther  west,  Butler  County  and  trending  toward  the  north.  De- 
velopment in  this  area,  however,  cannot  be  foreseen. 

In  summary,  the  Kansas  oil  fields  are,  in  all  probability,  beyond  the 
zenith  of  their  production.  Much  of  central  and  western  Kansas  may 
yet  be  tested,  but  conditions  are  difficult  or  impossible  to  predict,  and  the 
result  cannot  be  foreseen. 


108  RISE   AND   DECLINE   IN   PRODUCTION    OF   PETROLEUM 


Rise  and  Decline  in  Production  of  Petroleum  in  Ohio  and 

Indiana 

BY  J.  A.  BOWNOCKER,*  D.  Sc.,  COLUMBUS,  OHIO 
(New  York  Meeting,  February,  1920) 

THE  existence  of  petroleum  in  the  rocks  of  Ohio  and  Indiana  seems 
to  have  been  first  shown  by  wells  dug  for  salt.  The  fuel,  however,  was 
objectionable  owing  to  its  odor  and  inflammability.  Not  until  the  Drake 
well  was  drilled  in  1859  did  the  people  appreciate  the  value  of  rock  oil,  and 
then  they  at  once  began  plans  to  secure  the  coveted  fuel.  The  first 
successful  well  in  these  two  states  was  near  Macksburg,  in  southeast 
Ohio,  where  at  a  depth  of  59  ft.  (17  m.)  oil  was  found  in  commercial 
quantity  (1860).  A  year  later  this  fuel  was  secured  on  Cow  Run,  in  the 
same  county,  and  at  about  the  same  time  in  Noble,  Morgan  and  perhaps 
other  counties  in  that  part  of  Ohio. 

The  second  great  step  in  the  production  of  oil  in  Ohio  and  Indiana  was 
taken  in  1884  when  the  reservoir  of  natural  gas  in  the  Trenton  limestone  of 
northwest  Ohio  was  tapped,  and  where  a  year  later  oil  was  secured  in  the 
same  formation.  Petroleum  in  this  limestone  was  obtained  in  Indiana 
in  1889. l 

The  third  step  in  the  production  of  oil  in  Ohio  and  Indiana  is  associa- 
ted with  the  Clinton  sand  of  Ohio.  Natural  gas  in  large  volume  was  dis- 
covered in  that  rock  at  Lancaster,  in  1887,  and  the  area  has  been  extended 
until  it  has  become  the  largest  individual  producer  in  the  world.  The 
presence  of  natural  gas  in  such  great  volume  all  but  demonstrated  to  the 
driller  that  oil  lay  hidden  near  by.  Soon  the  search  for  it  was  started  but 
not  until  1899  was  petroleum  in  commercial  quantity  found  in  the  Clinton 
sand,  and  a  large  pool  was  not  located  in  it  until  1907. 

The  fourth  step  in  the  development  of  the  industry  was  taken  in  1913, 
when  the  pool  in  Sullivan  County,  in  western  Indiana,  was  opened.  The 
producing  rock  is  the  Huron  sandstone,  which  is  the  topmost  member  of 
the  Mississippian  system.2 


*  State  Geologist  and  Professor  of  Geology,  Ohio  State  University. 

1  Dept.  of  Geol.  and  Nat.  Res.  of  Indiana,  2Sth  Ann.  Rep.  (1903)  82. 

*  Edward  Barrett:  Dept.  Geol.  and  Nat.  Res.  of  Indiana,  ZSth  Ann.  Rep.  (1913) 
9-34. 


J.    A.   BOWNOCKER 


109 


TABLE  1. — Production  in  Ohio  and  Indiana 


1876. 
1885. 
1889. 
1896. 
1904. 
1914. 
1918. 


OHIO, 
BARRELS 

31,763 

661,580 

12,471,466 

23,941,169° 

18,876,631 

8,536,352 

7,285,005 


INDIANA, 
BARRELS 


33,375 

4,680,732 

11,339,124' 

1,335,456 

877,588 


TOTAL 
BARRELS 

31,763 

661,580 

12,504,841 

28,621,901 

30,215,755* 

9,871,808 

8,162,563 


«  Maximum  production  for  state. 

6  Maximum  production  for  the  two  states  combined. 

PRODUCTION  FROM  THE  TRENTON  LIMESTONE  IN  OHIO  AND  INDIANA 

When  natural  gas  was  discovered  in  the  Trenton  limestone  at  Findlay, 
Ohio,  in  1884,  and  petroleum  a  year  later,  it  marked  an  epoch  in  the 
geology  of  petroleum.  Heretofore  the  source  of  these  fuels  had  been  in 
sandstones  or  conglomerates,  and  limestones  were  regarded  as  non- 
petroliferous.  For  this  reason  the  new  field  was  looked  on  by  the  prac- 
tical oil  man  with  much  suspicion,  which  was  increased  when  he  noted 
the  dark  color  and  bad  smell  of  the  oil.  It  was  soon  found,  too,  that  the 
methods  of  refining  hitherto  practiced  would  not  apply,  which,  of  course, 


PRINCIPAL  PRODUCING  OIL  ROCKS  IN  OHIO  AND  INDIANA 


Pennsylvanian 


Mississippian 


Mitchell  sand  (Ohio) 

First  Cow  Run  or  Macksburg  140-ft.  sand  (Ohio) 

Macksburg  500-ft.  sand  (Ohio) 

Macksburg  800-ft.  sand  (Ohio) 

Huron  sand  (Indiana) 
Keener  sand  (Ohio) 
Big  Injun  sand  (Ohio) 
Berea  sand  (Ohio) 


Devonian Cornif erous  limestone  (Indiana) 

Silurian Clinton  sand  (Ohio) 

Ordovician Trenton  limestone  (Ohio  and  Indiana) 

was  another  objection  to  the  fuel.  However,  the  oil  had  a  market, 
which  insured  further  drilling.  Wells  were  completed  as  fast  as  the  tools 
could  be  forced  through  the  rocks  and  the  production  of  oil  increased 
at  a  rapid  rate.  In  fact,  the  supply  grew  faster  than  the  demand  so  that 
the  storage  of  the  fuel  became  a  serious  problem.  To  check  production, 
the  Standard  Oil  Co.  reduced  the  price  time  and  again  until,  in  July, 
1887,  it  was  listed  at  only  15  cents  per  barrel.  In  spite  of  this,  drilling 
continued  and  the  production  kept  apace.  The  development  of  an 
improved  method  of  refining  strengthened  the  market  for  the  crude  oil 


110 


RISE   AND   DECLINE   IN   PRODUCTION   OF  PETROLEUM 


and  the  price  advanced,  with  some  fluctuations,  until  at  present  (Octo- 
ber, 1919)  it  is  $2.48  per  barrel. 

While  the  Lima-Indiana  field  was  opened  34  years  ago,  drilling  has 
been  continuous  and  is  still  in  progress.  In  1917,  534  wells,  of  which  174 
were  producers,  were  drilled  in  Ohio  and  266,  of  which  174  were  producers, 
were  completed  in  Indiana.  The  magnitude  of  the  drilling  is  well  shown 


25 


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UJ 
CC 


20 


15 


o 

t/5 

z 
o 
=5 

I 
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o 

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o 
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Q. 


m  i£>  r~  co  o  o  — 
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o  —  ~~  ---  ---  — 

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YEARS 
FIG.  1. 

by  the  fact  that  from  June,  1905,  to  Dec.  31,  1917,  12,514  wells  were  sunk 
in  the  Ohio  part  of  the  field  and  15,005  on  the  Indiana  side.8  Barrett 
estimates  that  30,000  wells  have  been  drilled  to  the  Trenton  in  Indiana 
and  the  number  in  Ohio  must  have  been  larger  because  the  producing 
area  is  much  greater. 

With  Findlay  as  a  center,  drilling  was  carried  on  in  all  directions, 
but  it  was  soon  learned  that  the  producing  territory  had  narrow 
limits  along  an  east-and-west  line  and  that  it  was  continuous  in  a 


» Petroleum  in  1917.     U.  S.  Geol.  Survey  Mineral  Resources  (1919)  750. 


J.    A.   BOWNOCKER  111 

northeast-southwest  direction.  By  1890,  the  field  had  been  pretty 
definitely  delimited  and  was  found  to  form  an  arc  of  a  circle  from  the 
western  end  of  Lake  Erie  southwest  through  Wood,  Hancock,  Allen, 
Auglaize,  and  Mercer  Counties  to  the  Indiana  line,  which  it  later  crossed 
and  extended  slightly  northwest  to  near  Marion,  Grant  Co.  The  total 
length  of  the  field  is  about  150  miles  (241  km.)  but  the  width  varies 
greatly;  in  places  it  is  only  a  fraction  of  a  mile  while  elsewhere  it  may  have 
a  width  of  20  miles. 

The  maximum  production  from  the  Trenton  limestone  of  Ohio 
was  reached  in  1896;  it  was  20,575,138  bbl.  The  Indiana  part  of 
the  field,  as  it  was  developed  later,  did  not  attain  its  maximum  until  1904, 
when  it  produced  11,317,259  bbl.  Fig.  1  shows  the  rise  and  decline  of 
the  entire  field. 

The  size  of  the  wells  varied  greatly  but  the  maximum  seldom  reached 
10,000  bbl.  Initial  productions  of  from  100  to  500  bbl.  per  well,  however, 
were  common,  and  the  shallowness  of  the  wells  made  them  profitable 
though  the  price  of  oil  was  low.  Everywhere  salt  water  was  found,  and 
the  work  of  pumping  this  has  been  enormous.  Streams  were  made 
brackish  and  the  water  therefore  unfit  for  use.  The  oil  has  a  density  of 
from  36°  to  42°  Be*.,  and  is  consequently  heavier  than  the  Pennsylvania 
oil.  Its  base  is  chiefly  paraffin,  though  some  asphalt  is  present.  Sulfur 
is  an  objectionable  constituent.  The  oil  is  darker  than  the  Pennsyl- 
vania product  and  the  odor  more  disagreeable. 

Because  of  its  thickness  and  continuity,  the  Trenton  limestone  may 
be  thought  of  as  the  rock  floor  of  both  Ohio  and  Indiana.  It  rises  to 
the  surface  in  only  one  locality — the  Ohio  Valley  from  Coney  Island  (near 
Cincinnati)  to  Ripley,  Brown  County.  From  this  locality  it  dips  to 
the  east,  north,  and  west,  but  rises  to  the  south  and  forms  the  surface 
rock  in  part  of  the  blue-grass  region  of  Kentucky.  At  Findlay,  it  lies 
1092  ft.  (332  m.)  below  the  surface;  at  Columbus,  2035  ft.;  and  at 
Cleveland,  4445  ft.  In  Indiana  similar,  though  not  as  large,  variations 
are  found.  Everywhere  in  both  states,  outside  of  the  narrow  area  of 
outcrop  located  above,  the  Trenton  has  always  been  found  if  the  drill  has 
penetrated  to  its  horizon. 

In  thickness,  the  Trenton  shows  much  variation,  but  using  the  name  in 
its  older  and  broader  sense  the  rock  is  everywhere  measured  by  hundreds 
rather  than  by  tens  or  scores  of  feet.  Thus,  at  Findlay  its  thickness  is 
729  ft.  (222  m.)4;  at  Columbus,  475  ft.;5  and  at  Waverly,  in  southern 
Ohio,  808  ft.6 

The  composition  of  the  Trenton  limestone  varies  both  horizontally 

<D.  D.  Condit:  Am.  Jnl.  Sci.  (1913)  36,  125. 

'Edward  Orton:  Geol.  Survey  of  Ohio  (1888)  6,  107. 

•  J.  A.  Bownocker:  Geol.  Survey  of  Ohio  Bull.  12  [4]  (1910)  48. 


112  RISE   AND   DECLINE   IN   PRODUCTION   OF   PETROLEUM 

and  vertically.     Where  the  rock  yields  oil  or  gas  in  commercial  quantity, 
it  is  magnesian,  as  is  shown  by  the  following  analyses : 

CaCOi  MgCO»  INSOL.  RESIDUE   AljOs  AND  Fe2O 

Findlay,  Ohio 53.50  43.05            1.70              1.25 

Bowling  Green,  Ohio 51 . 78  36 . 80            4 . 89 

Lima,Ohio 55.90  38.85            0.75              2.94 

Kokomo,  Indiana 52.80  39.50            4.60              2.40 

In  places,  at  least,  the  Trenton  changes  rapidly  with  depth.  Thus, 
at  Bowling  Green  an  analysis  of  the  rock  from  100  ft.  (30  m.)  below  its 
top  showed  more  than  88  per  cent,  of  calcium  carbonate  and  less  than  7  per 
cent .  of  magnesium  carbonate,  while  the  top  beds  gave  less  than  42  per  cent . 
of  calcium  carbonate  and  nearly  37  per  cent,  of  magnesium  carbonate. 
Outside  of  the  producing  territory,  the  Trenton  appears  to  lose  its  mag- 
nesian character,  for  the  calcium  carbonate  rises  in  most  places  to  at 
least  75  per  cent,  of  the  rock.7  Since  there  is  an  increase  in  porosity  with 
magnesium  carbonate,  the  composition  of  the  rock  may  have  much  to  do 
with  its  capacity  to  store  the  oil. 

The  color  of  the  Trenton  limestone  is  dark  gray,  judging  from  pieces 
thrown  to  the  surface  when  the  wells  are  torpedoed.  It  is  finely  crystalline 
and  contains  numerous  veins  of  dolomite.  Cavities,  doubtless  the  work  of 
solution,  are  common  and  greatly  increase  the  storage  capacity  of  the  rock. 

The  depth  of  wells  usually  ranges  from  1000  to  1500  f  t.  (304  to  457  m.)  in 
Ohio;  in  Indiana  the  depth  averages  about  1000ft.  The  great  body  of  the 
oil  is  in  the  upper  50  ft.  of  the  reservoir  rock,  but  a  second  and  even  a 
deeper  pay  has  been  found  in  places ;  these,  however,  have  yielded  but 
little  oil.  Efforts  have  been  made  to  find  oil  in  rocks  below  the  Trenton, 
but  without  success.  In  a  well  drilled  near  Findlay,  Ohio,  in  1912, 
work  did  not  cease  until  the  tools  had  penetrated  the  rocks  to  a  depth  of 
2980  ft.;  granite  or  a  similar  rock  was  struck  at  2770  ft. 

The  thickness  and  structure  of  the  rocks  are  remarkably  uniform,  and 
while  there  is  considerable  variation  in  depth  of  wells,  it  results  almost 
wholly  from  the  anticlinal  structure.  Naturally,  wells  located  on  the 
top  of  the  arch  are  the  most  shallow.  Following  are  representative  well 
records  from  Ohio  and  Indiana: 

TABLE  2. — RECORDS  OF  OHIO  AND  INDIANA  WELLS 

OHIO  INDIANA 

THICKNESS,  THICKNESS, 

FEET  FEET 

Drift 43  Drift 50 

Monroe  limestone 107  Niagara  limestone 153 

Niagara  limestone 140  Cincinnati  shales 751 

Niagara  shale 13  Trenton  limestone  at 954 

Brassfield  limestone 89 

Gray  shale 47 

Red  shale 45 

Cincinnati  shales 706 

Trenton  limestone  at 1 190 

'  Edward  Orton:  Geol.  Survey  of  Ohio  (1888)  6,  103-104. 


J.    A.    BOWNOCKER  113 

The  petroleum  in  the  Lima-Indiana  field  is,  in  places  at  any  rate, 
closely  related  to  structure.  As  is  well  known,  the  Cincinnati  axis,  a 
broad  fold,  crosses  the  Ohio  River  about  25  miles  east  of  Cincinnati  and, 
extending  west  of  north  for  perhaps  40  miles,  bifurcates,  one  arm  running 
a  few  degrees  east  of  north  toward  the  western  end  of  Lake  Erie  and  the 
other  arm  west  of  north  toward  the  southern  end  of  Lake  Michigan.  In 
Lucas,  Wood,  Seneca,  and  Hancock  Counties,  Ohio,  the  principal  oil 
fields  are  on  the  summit  or  eastern  slope  of  this  arch.  Farther  southwest, 
in  Allen,  Mercer,  and  Auglaize  Counties,  Ohio,  the  productive  territory 
is  on  the  west  side  of  the  arch,  while  in  Indiana  it  is  on  the  north  side. 
The  Ohio  part  of  the  field  was  one  of  the  first  to  lend  support  to,  if  not 
to  demonstrate,  the  anticlinal  theory  that  has  recently  been  announced 
by  I.  C.  White. 

The  Lima-Indiana  field  passed  its  zenith  nearly  a  quarter  of  a  century 
ago.  It  is  still  an  important  producer  but  is  steadily  decreasing.  While 
new  wells  are  completed  by  the  hundreds  each  year,  these  by  no  means 
equal  the  number  of  old  wells  abandoned.  Manifestly  this  field  cannot 
be  relied  on  to  meet  the  present,  much  less  the  rapidly  growing,  demand 
for  petroleum. 

PRODUCTION  FROM  THE  CLINTON  SAND  FIELDS  IN  OHIO 
The  Clinton  sand  nowhere  outcrops  in  Ohio;  hence  our  knowledge  of 
it  has  been  obtained  entirely  from  the  drill.  The  rock  was  first  struck  at 
Lancaster,  in  1887,  and  was  considered  limestone,  but  this  error  was  soon 
corrected.  While  still  called  Clinton,  it  has  been  pretty  definitely  shown 
that  the  rock  forms  a  part  of  the  underlying  formation,  the  Medina.8 
The  drill  has  demonstrated  that  the  Clinton  sand  does  not  underlie  the 
western  half  of  the  state  and  that  its  place  is  there  occupied  by  shales. 
Since  the  rocks  in  eastern  Ohio  dip  to  the  southeast,  the  horizon  of 
the  Clinton  sand  is  found  at  increasing  depths  as  the  Ohio  River  is 
approached.  Its  position  at  Wheeling  is  about  6560  ft.  (1999  m.)  below 
the  Ohio  Valley,  though  the  drill  has  not  penetrated  to  so  great  a  depth 
at  that  place.  While  it  is  probable  that  the  Clinton  sand  underlies 
eastern  Ohio,  its  presence  has  not  been  demonstrated  in  the  counties  east 
of  Tuscarawas,  Muskingum,  Athens,  and  Gallia.  Natural  gas  is  now 
secured  in  this  sand  in  Tuscarawas  County  at  a  depth  of  nearly  4000  ft., 
which  is  the  deepest  source  of  either  oil  or  gas  in  Ohio. 

The  Clinton  sand  is  usually  light  colored  and  clean,  but  in  places  it  is 
brick-red.  The  range  in  thickness  is  generally  from  10  to  40  ft.  (3  to 
12  m,)  but  the  maximum  occasionally  reaches  100  ft.  Along  its  western 
edge,  the  sand  is  thinner  and  somewhat  patchy.  According  to  the  tes- 
timony of  drillers,  the  sand  is  free  from  water  when  first  penetrated, 
making  the  territory  unique  among  the  oil  fields  of  Ohio. 

8  J.  A.  Bownocker:  Econ.  Geol  (1911)  6,  37. 


114 


RISE   AND    DECLINE   IN   PRODUCTION    OF   PETROLEUM 


Petroleum  is  now  secured  in  the  Clinton  sand  of  Ohio  in  Hocking, 
Perry,  Fairfield,  Muskingum,  and  Wayne  Counties  and,  to  a  very  small 
extent,  in  several  others.  The  pools,  however,  are  nearly  all  small,  the 
largest  being  in  Perry  County.  The  oil  has  a  density  of  from  35  to  46° 
Be"  and  much  of  it  is  of  Pennsylvania  grade.  Few  wells  have  had  an 
initial  production  as  large  as  1000  bbl.  per  day;  in  fact,  those  starting  at 
as  much  as  500  bbl.  have  been  rare.  The  production,  however,  is  well 
maintained,  which  helps  compensate  the  operator  for  his  great  labor  and 
expense.  The  maximum  production  of  the  sand  was  about  1,300,000 
bbl.  per  year,  but  it  is  now  smaller.  Much  time  and  money  have  been 
expended  in  an  effort  to  extend  the  producing  territory  to  the  east,  but  the 
results  have  been  unsuccessful. 

The  depth  of  wells  varies  with  surface  altitude  and  with  dip.  Near 
Pleasantville,  Fairfield  County,  the  depth  to  the  producing  sand  is  about 
2325  ft.,  while  near  Crooksville,  in  the  eastern  part  of  Perry  County,  the 
depth  is  more  than  3400  ft.  These  two  wells  represent  very  well  the 
present  extremes  for  oil  production  from  this  sand  in  Ohio. 

The  position  of  the  Clinton  sand  is  usually  from  100  to  150  ft.  (30 
to  45  m.)  below  the  Silurian  limestone,  or  "Big  lime"  as  the  rock  is 
known  by  the  driller,  and  hence  it  is  very  easy  for  him  to  determine  his 
position  with  reference  to  the  desired  sand.  The  following  well  records, 
one  in  southern  and  the  other  in  northern  Ohio,  show  very  well  the  rock 
succession: 


Perry  ( 

bounty 

Wayne 

County 

Thickness, 
Feet 

To  Bottom, 
Feet 

Thickness, 
Feet 

To  Bottom, 
Feet 

Mantle  rock  

55 

55 

57 

57 

Big  Injun  sand. 

100 

235 

Berea  sand  

33 

718 

30 

495 

Bedford  and  Ohio  shales 

1032 

1750 

1335 

1830 

Devonian    and    Silurian    lime- 
stones   

798 

2548 

1085 

2915 

Clinton  sand  

33 

2708 

31 

3135 

The  Bedford  and  Ohio  shales  form  a  great  wedge-shaped  mass  with 
the  apex  in  central  Ohio  and  the  base  near  Wheeling,  W.  Va.,  where  its 
thickness  is  at  least  2500  ft.  The  Devonian  and  Silurian  limestones 
increase  in  thickness  to  both  the  east  and  the  north.  At  Columbus 
they  measure  770  ft.;  at  Zanesville,  1012  ft.;  and  at  Wheeling,  1900  ft. 
To  the  northeast,  the  thickness  increases  from  770  ft.  at  Columbus  to 
1085  ft.  in  Wayne  County,  and  reaches  a  maximum  of  1400  ft.  at  Cleve- 
land. It  is  the  increasing  thicknesses  of  these  rocks  that  give  the  under- 
lying Clinton  sand  its  sharp  dip,  hence  its  rapidly  increasing  depth. 


J.    A.   BOWNOCKEK  115 

The  structure  of  this  sand,  in  its  broader  aspect  at  any  rate,  is  easily 
stated.  It  dips  to  the  southeast,  while  in  the  longitude  of  Columbus  it 
thins  and  is  replaced  by  shales.  It  may,  therefore,  be  compared  with 
one  arm  of  an  anticline.  Along  the  western,  or  higher,  part  of  this  arm, 
great  volumes  of  natural  gas  have  been  found;  while  a  little  farther  east, 
and  hence  at  a  lower  level,  reservoirs  of  oil  have  been  located.  How  the 
oil  got  into  its  position  is  not  clear,  for  the  absence  or  scarcity  of  water 
deprives  us  of  the  usual  agent.  Neither  is  it  plain  how  the  oil  is  held  in 
its  present  location,  but  possibly  it  rests  in  shallow  basins. 

PRODUCTION  FROM  THE  CORNIFEROUS  LIMESTONE  OF  INDIANA 
The  Corniferous  limestone  that  forms  the  base  of  the  Devonian  in 
Ohio  and  Indiana  is  a  source  of  petroleum  in  the  latter  state,  but  not  in 
the  former.  However,  even  in  Indiana,  the  reputation  of  this  rock  as  a 
source  of  fuel  rests  on  a  single  well,  the  Phoenix,  which  was  drilled  in 
Terre  Haute  in  1889  and  is  credited  with  being  the  best  payer  ever 
drilled  in  the  state.9  The  limestone  was  struck  at  a  depth  of  1660  ft.  and 
for  at  least  12  years  the  production  averaged  1000  bbl.  of  oil  per  month. 
In  1908,  it  averaged  340  bbl.  per  month;  few  wells  in  this  country  have 
so  large  a  daily  yield  after  30  years  continuous  production.  l°  Later,  a  few 
small  wells  were  secured  in  the  same  formation  south  and  southeast  of 
Terre  Haute,  but  were  it  not  for  the  remarkable  Phoenix  well,  the  terri- 
tory would  not  be  mentioned. 

PRODUCTION  FROM  MISSISSIPPIAN  AND  PENNSYLVANIAN  SANDSTONES 

IN  OHIO  AND  INDIANA 

Since  these  producing  rocks  have  similar  physical  and  chemical  proper- 
ties and  representatives  of  both  groups  may  be  yielding  oil  in  the  same 
territory,  they  will  be  reviewed  together.  Next  to  the  Trenton  lime- 
stone, they  have  been  the  largest  producers  of  oil  in  each  state,  and  at  the 
present  time  they  are  the  largest  source  in  Ohio. 

The  producing  territory  in  Ohio  is  restricted  to  the  eastern  half ,  since 
that  is  the  only  part  where  rocks  of  this  age  are  present.  Trumbull  and 
Lorain  have  been  the  northernmost  counties,  though  neither  was  ever  a 
large  producer.  The  large  sources  of  oil,  now  as  in  the  past,  are  Jefferson, 
Harrison,  Belmont,  Monroe,  Noble,  Washington,  Morgan,  and  Perry 
Counties,  with  Monroe  and  Washington  far  in  the  lead.  As  previously 
stated,  drilling  in  this  territory  started  in  1860  and  is  still  in  progress. 
In  1891,  oil  in  the  deeper  sands  of  Monroe  County  was  first  secured  and 
that  marked  the  beginning  of  the  large  source  of  oil  in  eastern  Ohio. 
Most  of  the  pools  are  small,  but  some  of  these  in  Monroe  and  Washing- 
ton Counties  compare  favorably  in  size  with  the  largest  of  the  Appa- 

»  W.  S.  Blatchley:  Dept.  of  Geol.  and  Nat.  Res.  of  Indiana,  25th  Ann.  Rep.  (1900) 
517.    Also  33rd  Ann.  Rept.  (1908)  373. 

10  This  well  is  still  producing  between  3000  and  3500  bbl.  per  year. 


116 


RISE   AND   DECLINE   IN   PRODUCTION   OF  PETROLEUM 


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THE  PETROLEUM  FIELDS 
OF  EASTERN  OHIO  IN  I9f9. 


Fio.  2. 


J.    A.   BOWNOCKER  117 

lachian  field.  Wells  have  been  sunk  in  great  numbers  and  no  large  area 
remains  untested.  On  the  Woodsfield  quadrangle  alone  about  2000  wells 
have  been  drilled,  and  the  number  is  very  large  on  numerous  other 
quadrangles  in  Monroe,  Washington,  and  Morgan  Counties.  The  future 
discovery  of  large  pools  is  therefore  very  improbable,  and  the  production 
of  5,586,433  bbl.  in  1903  will  probaby  not  be  equaled. 

In  Indiana,  the  producing  territory  in  rocks  of  this  age  lies  chiefly  in 
Gibson  and  Sullivan  Counties  in  the  southwestern  part  of  the  state. 
This  territory  assumed  commercial  proportions  in  1913,  and  in  1914  the 
production  of  the  state  increased  40  per  cent,  the  increase  being  from  these 
two  counties.  Later,  oil  was  found  in  Pike  and  Daviess  Counties,  and 
the  territory  to  be  prospected  was  thus  largely  increased.  Of  the  266 
wells  drilled  for  oil  in  Indiana  in  1917,  187  were  in  these  four  counties. 
Notwithstanding  the  yield  from  this  territory,  the  production  for  the  state 
has  decreased,  that  for  1917  being  smaller  than  for  any  year  since  1892. 
While  the  outlook  for  an  increased  production  from  southwest  Indiana  is 
not  so  unfavorable  as  it  is  from  the  Trenton  limestone,  the  prospect  is 
not  very  promising. 

The  following  composite  record  of  two  wells  in  Washington  County 
shows  the  important  producing  sands  in  Ohio  and  their  relative  positions: 

THICKNESS,      To  BOTTOM, 
FEET  FEET 

Pennsylvanian. 

Meigs  Creek  (Macksburg)  or  No.  9  coal 5  15 

First  Cow  Run  or  Macksburg  140-ft.  sand 35  378 

Macksburg  500-ft.  sand 17  702 

Macksburg  800-ft.  sand 51  826 

Salt  sand 190  1095 

Mississippian. 

Mountain  limestone  (Big  lime) 35  1325 

Keener  sand 55  1430 

Big  Injun  and  Squaw  sands 115  1545 

Berea  sand 14  1953 

Strenuous  efforts  have  been  made  by  drillers  and  producers  to  find 
below  the  Berea  sands  that  are  the  equivalent  of  the  deep  sands  of 
Pennsylvania,  but  it  has  been  proved  that  when  the  Berea  is  passed, 
in  eastern  Ohio,  the  last  hope  of  securing  oil  is  gone.  The  Clinton 
sand  should  be  present,  but  it  lies  so  deep  that  the  drill  has  not  as 
yet  reached  it. 

The  persistence,  texture,  and  thickness  of  the  sands  in  eastern  Ohio 
vary  greatly.  The  deepest  sand,  the  Berea,  may  be  put  in  a  class  by  it- 
self for  persistence  and  texture.  It  is  extensively  quarried  near  Cleveland 
and  it  outcrops  in  the  middle  of  Ohio  from  Lake  Erie  south  to  the  Ohio 
River.  From  its  outcrop,  the  sand  dips  to  the  southeast  and  it  is  almost 
invariably  present  in  its  proper  place.  In  thickness,  the  usual  range  is 
from  10  to  40  ft.;  but  in  northern  Ohio,  much  greater  measurements  have 
been  made.  Lying  interbedded  in  shales,  the  Berea  is  easily  recognized 


118  RISE   AND   DECLINE   IN   PRODUCTION   OF   PETROLEUM 

and  is  an  important  guide,  or  key,  rock  of  the  driller.  While  this  sand  is 
coarse  grained,  it  is  much  less  so  than  the  higher  sands  of  the  eastern 
part  of  the  state.  The  workmen  report  it  much  harder  to  drill  than  the 
overlying  sands,  and  it  therefore  receives  larger  charges  in  torpedoing. 
The  Berea  is  productive  in  spots  over  much  of  eastern  Ohio.  In  counties 
north  of  Belmont  and  Guernsey,  it  is  the  only  source  of  oil,  and  it  is  of  still 
more  importance  farther  south.  Nevertheless  the  total  yield  from  this 
formation  is  not  large,  and  it  is  greatly  surpassed  by  the  Keener  and  Big 
Injun  sands.  v. 

The  Big  Injun  and  Keener  sands  are  the  largest  producers  of  oil  in 
eastern  Washington  and  in  Monroe  County  where  they  are  at  their  best. 
Where  these  sands  outcrop  in  the  middle  of  Ohio,  they  are  pebbly  or 
coarse  grained  and  constitute  the  Black  Hand  and  Logan  formations. 
Under  cover,  the  same  texture  is  maintained  and  the  rocks  yield  readily 
to  the  drill;  their  storage  capacity  is  large.  These  sands  are  everywhere 
present  where  due,  but  they  are  not  so  sharply  delimited  above  and 
below  as  is  the  Berea. 

The  Mountain  limestone,  or  Big  Lime,  where  present,  is  an  excellent 
guide,  or  key,  rock  of  the  driller.  It  is  well  developed  in  the  eastern  part 
of  Washington  and  in  the  southern  half  of  Monroe  County,  but  from  there 
it  thins  rapidly  to  the  north  and  west  and  is  rarely  if  ever  reported.  Its 
thickness  seldom  reaches  100  ft.  Along  its  outcrop  in  Muskingum,  Perry, 
and  other  counties  this  reck  is  known  as  the  Maxville  limestone.  The 
Big  Lime  is  not  a  large  source  of  oil,  but  an  occasional  producer  is  gotten  in 
it.  The  term  Big  Lime,  however,  is  used  by  the  drillers  for  two  entirely 
different  rocks  or  groups  of  rocks  in  Ohio.  As  the  following  table  shows, 
the  upper  one  forms  the  top  of  the  Mississippian  system;  while  the  lower 
one  belongs  to  the  Devonian  and  Silurian  systems. 

Maxville  limestone,  the  Big  Lime  of  southern  Ohio. 


Mississippian  (Lower  Carbon- 
iferous)   


f  Keener  sand 
Black  Hand  and  Logan. .  |  Big  Injun  sand 

I  Squaw  sand 
Berea  sand 


Devonian , 


Silurian 


Olentangy  and  Ohio  shales 
Delaware  limestone 
Columbus  limestone 
Monroe  limestone 
Niagara  limestone 
Brassfield  limestone 


The  Big   Lime   of   the 
Clinton  sand  fields. 


The  sands  of  the  Pennsylvanian  are  much  alike  in  properties.  They 
are  coarse  grained,  light  colored,  open  textured,  and  easy  to  drill.  Lack 
of  persistence  is  a  striking  feature;  this  is  particularly  true  of  the  First 
Cow  Run  sand.  They  are  beach  or  near-shore  deposits,  and  their  varia- 
tions are  a  result  of  changes  in  direction  and  in  strength  of  movement 
of  the  water. 


DISCUSSION  119 

The  sands  of  the  Pennsylvania!!  are  not  productive  except  in  the 
southeastern  part  of  Ohio.  The  First  Cow  Run,  or  Macksburg  140-ft., 
sand  is  an  important  source  of  oil  in  Morgan,  Washington,  and  Noble 
Counties.  Its  place  is  in  the  Conemaugh  formation  and  about  160  ft. 
below  the  Pittsburgh  coal.  The  Macksburg  500-ft.  and  the  Macksburg 
800-ft.  sands  are  still  more  restricted  in  their  producing  area,  which  is 
limited  to  northern  and  central  Washington  County. 

The  variation  in  depth  of  wells  is  notable.  The  range  is  from  12  ft. 
(3.6  m.)  to  2200  ft.  (670  m.)  and  one  of  only  38  ft.  is  still  being  pumped. 
Compared  with  other  important  fields,  the  wells  have  been  small  pro- 
ducers. Very  few  have  had  an  initial  production  as  large  as  500  bbl. 
per  day,  and  the  maximum  was  about  2500  bbl.  The  wells  are  long  lived, 
which  in  a  measure  compensates  for  their  small  size.  Thus  one  well,  only 
98  ft.  deep,  near  Joy,  Morgan  County,  is  said  to  have  been  producing 
continuously  since  1872.  The  oil  is  nearly  all  of  Pennsylvanian  grade  and 
ranges  in  density  from  42°  to  50°  Be".  The  color  is  dark  green,  red,  or 
black.  Salt  water  is  everywhere  present. 

The  structural  features  of  the  oil-producing  sands  in  eastern  Ohio  are 
not  conspicuous.  The  rocks  dip  to  the  southeast  at  a  varying  rate,  in 
most  places  from  25  to  40  ft.  per  mi.  A  few  well-marked  anticlines  or 
domes  are  found,  the  most  conspicuous  being  the  Burning  Springs  anti- 
cline, which  crosses  the  Ohio  Valley  about  12  miles  east  of  Marietta.  An- 
other  one  is  at  Cambridge,  but  neither  oil  nor  gas  in  large  quantity  has 
been  found  with  it.  The  Cow  Run  pool,  in  Washington  County,  is  on  a 
well-marked  dome.  Smaller  folds  have  been  located  in  Washington, 
Belmont,  Harrison,  and  other  counties,  and  oil  or  gas  in  most  cases  has 
been  found  beneath  them.  Some  of  the  larger  fields,  however,  are  not 
known  to  be  on  structures  of  this  kind.  The  contour  maps  of  the  oil  sands , 
which  the  Federal  Survey  has  been  issuing  in  recent  years,  show  oil  in 
almost  all  positions  except  synclines.  Probably  the  three  most  important 
features  that  determine  the  presence  of  oil  are  structure,  texture,  and  salt 
water. 

Within  the  past  few  years  Smith  and  Dunn,  of  Marietta,  Ohio,  have 
patented  a  process  for  increasing  the  production  of  oil  wells  that  have 
been  pumped.  They  force  air  into  the  oil  sand  under  a  pressure  that 
varies  in  most  places  from  40  to  350  Ib.  to  the  square  inch.  This,  it  is 
stated,  increases  the  production  on  an  average  from  100  to  150  per  cent., 
with  a  maximum  of  800  per  cent.11 

DISCUSSION 

L.  S.  PANYITY,*  Columbus,  0.  (written  discussion). — Under  the 
subdivision  of  "Production  from  the  Clinton  sand  field  in  Ohio,"  relative 

"  J.  O.  Lewis:  U.  S.  Bureau  of  Mines  Bull.  148  (1919). 
*  Chief  Geologist,  Ohio  Fuel  Supply  Co. 


120  RISE   AND    DECLINE   IN   PRODUCTION   OF   PETROLEUM 

to  the  depth  to  the  sand  in  Tuscarawas  County,  the  wells  are  in  all  cases 
at  least  4500  ft.  (1371  m.)  in  depth  and  the  deepest  well  producing  oil  or 
gas  from  the  Clinton  found  that  sand  at  a  depth  of  over  5000  feet. 

In  regard  to  "how  the  oil  got  into  its  position,"  the  possibility  that 
the  main  accumulations  rest  in  shallow  basins  is  untenable,  as  structure 
maps  indicate  homoclinal  accumulations.  The  main  controlling  factor 
is  lensing  and  differential  cementation.  This  belief  is  further  strengthened 
by  the  presence  of  scattered  gas  wells  down  dip  from  the  oil.  The  pres- 
ent eastern  edge  of  the  oil  fields  in  the  Clinton  is  already  at  great  depths, 
which  fact  has  prevented  extensive  prospecting  still  farther  down  dip, 
but  it  is  a  question  of  time  when  deeper  tests  will  be  made.  If  the 
water  conditions  remain  as  they  are,  water  thus  far  having  been  found 
in  but  a  few  wells,  the  homocline  at  lower  structural  levels  promises 
that  newer  pools  may  be  opened  up.  Another  point  in  favor  is  that  the 
Clinton,  as  well  as  all  other  formations,  being  deposited  on  the  eastern 
flank  of  the  Cincinnati  anticline,  at  the  same  time  when  the  folding  was 
taking  place,  i.e.,  folding  and  deposition  being  contemporaneous,  the 
formations  can  be  expected  to  thicken  away  from  the  axis.  Thus,  we 
may  expect  a  thicker  Clinton  stratum  farther  east  and  down  dip.  Should 
an  abundance  of  water  make  its  appearance  in  the  formation,  structural 
conditions  must  be  more  favorable;  and  as  we  have  more  pronounced 
structures  eastward,  as  noted  from  surface  outcrops,  they  will  offer 
sufficient  inducements  for  drilling. 

Relative  to  the  structure  of  the  eastern,  or  shallow  sand,  fields,  especi- 
ally the  effect  of  the  Cambridge  anticline  upon  production,  the  older 
surveys  have  indicated  this  arch  to  take  a  northeast-southwest  direction. 
The  writer's  study  of  this  structure  indicates  that  the  main  fold  takes  a 
southern  and  a  little  easterly  direction;  commencing  at  Cambridge,  it 
passes  through  Caldwell  and  Macksburg,  and  apparently  extends  farther 
southward  in  the  direction  of  the  Burning  Springs  anticline  of  West 
Virginia,  which  may  prove  to  be  a  continuation  of  this  fold.  The  south- 
ward plunging  axis  brings  gas  accumulations  just  south  of  Cambridge 
and  oil  pools  are  found  all  along  this  axis  as  far  as  the  Ohio  boundary 
line  at  the  Ohio  River;  thus  we  have  good  oil  pools  all  along  it  south  of 
Caldwell,  including  the  well-known  Macksburg  pool  which  is  known  to  all 
oil  men.  The  secondary  folds,  which  radiate  from  the  main  fold  in  a 
northeasterly  direction,  also  control  the  accumulations  to  the  east.  It 
is  the  writer's  opinion  that  the  greatest'number  of  accumulations  have 
been  directly  caused  by  the  general  main  fold  known  as  the  Cambridge 
anticline  and  the  secondary  folds  radiating  from  it. 

It  is  true  that  there  are  many  good  pools  not  so  situated,  where  a 
different  explanation  is  needed.  North  and  west  of  the  city  of  Cambridge 
small  scattered  gas  wells  are  found  but  not' what  may  be  considered  as 
real  pools.  Here  the  anticline  loses  its  prominence  and  the  sand  condi- 


DISCUSSION  121 

tions  are  entirely  different;  this  phase  has  been  discussed  by  the  writer12 
in  a  former  paper. 

The  Scio  pool  is  often  quoted  as  one  of  the  large  " off-structure" 
accumulations.  The  main  controlling  factor  here  is  the  water  level 
on  a  homocline  above  which  the  oil  is  found.  That  the  sand  conditions 
are  not  the  main  factors  at  Scio  is  brought  out  by  the  fact  that  the  per- 
centage of  dry  holes  inside  the  producing  territory  is  exceedingly  small. 
We  have  here  a  very  extensive  formation,  what  may  be  called  a  sheet  sand 
on  a  somewhat  smaller  scale  than  is  generally  understood.  Oil  accumu- 
lates above  the  water  and  is  found  in  almost  every  well  drilled  above  the 
water  level,  up  the  dip,  until  gas  showings  are  encountered.  Corning 
offers  a  similar  case,  where  the  water  level  is  a  factor,  however;  the 
normal  dip  is  arrested  to  a  considerable  extent,  giving  a  terrace  structure, 
and  several  smaller  pools  northeastward  and  along  the  strike  are  claimed 
to  be  on  small  domes. 

There  have  been  very  few  quadrangles  mapped  by  the  Federal 
and  State  surveys,  thus  the  impression  gained  from  them  should  not  be  a 
criterion  for  the  entire  shallow  sand  production  of  the  state.  One 
noticeable  feature  of  the  so-called  "off-structure"  accumulations  here  is 
the  way  the  pools  adhere  closely  to  the  direction  of  the  strike,  and  that 
production  is  found  along  certain  structural  levels,  which  is  very  evident, 
even  though  there  may  be  considerable  barren  areas  between  pools. 
In  that  section  of  the  state  where  the  structural  conditions  are  homoclinal, 
the  prospector  will  do  well  to  pay  strict  attention  to  these  apparent 
producing  levels,  and  also  to  make  a  careful  study  of  lensing. 

12  Trans.  (1919)  61,  478. 


122  OIL   FIELDS   OF   KENTUCKY   AND   TENNESSEE 


Oil  Fields  of  Kentucky  and  Tennessee 

BY  L.  C.  GLENN,*  Ph.  D.,  NASHVILLE,  TENN. 

(New  York  Meeting,  February.  1920) 

IN  THE  preparation  of  this  paper  the  writer  has  drawn  freely  upon 
the  writings  of  Orton,  Munn,  Shaw,  Mather,  Miller,  Hoeing,  St.  Clair, 
Jillson,  and  others,  as  well  as  upon  his  own  personal  knowledge  of  the 
fields  of  both  states.  It  is  to  be  regretted  that  certain  data  gathered  by 
him  and  his  assistants  last  fall  are  not  available  for  publication. 

OIL  IN  TENNESSEE 

A  few  wells  drilled  for  brine  for  salt  making  in  Tennessee  between  1820 
and  1840  obtained  oil,  but  no  definite  search  was  made  for  oil  until  just 
after  the  close  of  the  Civil  War.  Active  drilling  was  then  begun  in 
Over  ton  and  counties  southwest  of  it  on  the  eastern  half  of  the  High- 
land Rim.  A  number  of  strikes  were  made  at  shallow  depths  in  the 
basal  part  of  the  Mississippian  but  the  wells  were  soon  exhausted  and 
abandoned.  Drilling  was  revived,  about  1892,  when  the  Spurrier  dis- 
trict in  Pickett  County  was  developed  and  was  followed  by  the  Riverton 
district  in  the  same  county  in  1896.  A  pipe  line  was  laid  from  the  Wayne 
County,  Ky.,  fields  and  about  60,000  bbl.  of  oil  were  run  before  a  very 
heavy  slump  in  the  production,  a  failure  to  find  an  extension  of  the  field, 
and  excessive  local  taxation  caused  the  removal  of  the  pipe  line  in  1906. 
There  was  then  no  production  in  Tennessee  until  the  discovery,  in  1915, 
of  oil  near  Oneida,  Scott  Co.,  at  about  950  ft.  (289  m.)  in  fissures  in 
the  Newman  or  St.  Louis  limestone.  This  field,  however,  soon  failed 
and  was  abandoned. 

In  1916,  oil  was  found  at  Glen  Mary,  Scott  Co.,  in  the  Newman  lime- 
stone at  a  depth  of  1232  ft.  (375  m.)  A  number  of  wells  have  since 
been  drilled  there,  some  of  which  were  dry  while  others,  close  by,  were 
producers.  The  largest  one  yielded,  at  first,  about  340  bbl.  per  day  and 
produced  for  several  months,  when  it  suddenly  went  dry.  Several  of  the 
first  wells  began  at  6  or  8  bbl.  per  day  and  are  still  maintaining  that 
output.  Production  is  from  a  fissured  part  of  the  limestone  and  varies 
greatly  in  accordance  with  the  size  and  extent  of  the  ramification  of  the 

*  Consulting  Oil  Geologist  and  Professor  of  Geology,  Vanderbilt  University. 


L.   C.   GLENN  123 

fissures.  In  some  areas,  the  limestone  has  no  fissured  zone  and  wells  go 
through  it  without  obtaining  even  a  show  of  oil.  Fissuring,  when  present 
is  not  always  at  the  same  horizon  in  the  limestone  and  failure  to  obtain 
a  well  in  one  location  does  not  necessarily  mean  that  the  next  location  may 
not  be  a  successful  producer.  The  production  at  present  is  probably 
not  over  1000  bbl.  a  month.  The  oil  is  shipped  to  Somerset,  Ky.,  in  tank 
cars  and  there  delivered  to  the  Cumberland  pipe  line. 

The  limestone  in  which  the  oil  occurs  has,  so  far  as  has  been  ascer- 
tained, a  monoclinal  structure  and  rises  gently  to  the  west.  There  is  only 
a  little  gas  with  the  oil  and  little  or  no  salt  water  is  encountered.  No 
production  curves  can  be  given  since  the  wells  vary  greatly.  Some  decline 
rapidly  and  fail  in  a  few  months  while  others  show  scarcely  any  decline 
after  several  years  and  bid  fair  to  have  a  long  life  as  pumpers  of  about 
6  to  8  bbl.  per  day.  The  gravity  is  from  36°  to  38°  Baume*. 

There  is  now  considerable  activity  in  both  leasing  and  drilling,  espe- 
cially in  the  western  half  of  the  Highland  Rim,  west  and  northwest  of 
Nashville,  although  the  eastern  and  southern  parts  of  this  Rim  are  also 
receiving  some  attention.  The  surface  of  the  Highland  Rim  is  almost 
everywhere  of  Mississippian  age  and  is  underlaid,  at  a  maximum  depth 
of  not  more  than  a  few  hundred  feet,  by  the  Chattanooga  black  shale. 
Oil  shows  are  often  found  just  above  or  just  below  this  shale.  Much  of 
the  activity  has  been  stimulated  by  the  finding  of  oil  in  Allen  County, 
Ky.,  under  geological  conditions  very  similar  to  those  that  obtain  in  the 
adjacent  Highland  Rim  section  of  Tennessee. 

There  has  been  occasional  deep  drilling  in  Tennessee  for  a  number  of 
years,  especially  in  the  Central  Basin,  where  the  surface  rocks  are  of 
Ordovician  age,  in  the  hope  of  obtaining  a  deep  pay  usually  spoken  of  as 
the  Trenton.  All  such  attempts  in  this  part  of  the  state  have  so  far 
failed.  There  have  been  a  few  slight  shows  and  a  little  gas  has  been 
found,  but  no  good  sand  has  been  encountered.  The  only  Ordovician 
production  from  Tennessee  has  been  that  in  Pickett  County. 

A  half  dozen  holes  or  more-have  been  bored  in  the  last  10  years  in  the 
western  part  about  Memphis,  and  to  the  north  of  it,  near  the  axis  of  the 
great  trough  in  which  the  Gulf  embay ment  deposits  have  been  laid  down. 
These  wells  usually  range  from  2000  to  3000  ft.  (609  to  914  m.)  in  depth 
and  several  of  them  reported  shows  of  oil  or  gas  in  the  lower  part  of  the 
section.  Very  recently,  activity  in  this  part  of  the  state  has  been  re- 
vived and  preparations  for  further  deep  testing  of  the  embayment  de- 
posits in  the  vicinity  of  Reelfoot  Lake  in  the  northwestern  corner  of 
the  state  are  now  being  made. 

The  history  of  attempts  at  oil  production  in  Tennessee  give  meager 
data  on  which  to  base  any  predictions  of  a  large  future  oil  production. 
No  well-defined  oil  sands  of  any  considerable  extent  are  known,  although 
large  areas  of  the  Newman  limestone  exist  beneath  the  Cumberland 


124  OIL  FIELDS   OP  KENTUCKY  AND  TENNESSEE 

plateau,  under  conditions  very  similar  to  those  at  Glen  Mary,  and 
remain  untested  by  the  drill.  Should  portions  of  these  be  notably 
fissured,  they  might  furnish  an  oil  field  of  much  importance.  It  is 
entirely  possible  that  oil  may  be  found  in  various  parts  of  the  High- 
land Rim,  either  in  the  Waverly  rocks  close  above  the  Chattanooga 
black  shale  or  in  Onondagan  or  Silurian  limestones  close  beneath  it. 
Such  rocks  appear  to  the  writer  as  the  most  promising  for  further 
drilling.  Oil  is  much  less  probable  in  the  Ordovician  rocks,  since  sand 
and  other  conditions  do  not  usually  seem  favorable  there. 

The  surface  of  the  Cumberland  plateau  consists  of  Pennsylvanian 
sandstones  and  shales  of  Pottsville  age  that  attain  a  maximum  thick- 
ness of  1000  ft.  (304  m.)  or  slightly  more,  beneath  the  general  plateau 
level.  So  far,  there  is  no  evidence,  either  from  occasional  wells  that 
have  gone  through  them  or  from  their  character  as  they  outcrop  on 
either  side  of  the  plateau,  that  the  Pottsville  rocks  contain  oil  in 
Tennessee.  Should  it  occur,  it  would  most  probably  be  found  in  that 
portion  nearest  the  Kentucky  line,  as  oil  is  obtained  from  several  Potts- 
ville horizons  in  Knox  County,  Ky.,  not  far  to  the  northeast. 

The  Gulf  embayment  sands  and  clays  of  western  Tennessee  attain 
a  thickness  in  excess  of  2500  ft.  (762  m.),  and  may  be  3500  ft.  (1066  m.) 
thick  along  the  axis  of  the  trough,  before  the  Paleozoic  floor  on  which 
they  rest  has  been  reached.  The  lower  part  of  these  embayment  rocks 
are  of  Cretaceous  age  and  are  the  equivalents  of  the  rocks  that  yield 
oil  and  gas  in  northwestern  Louisiana.  It  is  possible  that  they  may 
contain  oil  in  western  Tennessee,  although  structural  relations  are  so 
obscured  by  a  blanket  of  surficial  sands  and  by  the  general  flatness  of 
the  region  that  drilling  there  must  be  largely  a  matter  of  chance  and 
success  mainly  the  result  of  luck.  It  is  further  possible  that  some  part 
of  the  old  Paleozoic  floor  beneath  the  embayment  deposits  may  contain 
oil,  although  there  is  no  means  of  determining  either  the  lithologic 
character  or  the  structure  of  the  older  rocks  from  surface  inspection. 
Where  they  go  under  the  embayment  deposits  near  the  Tennessee 
river,  they  vary  in  age  from  Silurian  to  Mississippian.  Their  surface 
is  usually  regarded  as  a  beveled  erosional  one,  so  that  it  is  probable  that 
the  floor  of  the  embayment  may,  in  the  deeper  parts,  be  composed  of 
Ordovician  rocks. 

OIL  IN  KENTUCKY 

Oil  is  produced  in  Kentucky  in  a  large  number  of  separate  areas, 
most  of  them  small.  They  are  widely  scattered  through  the  east  central, 
eastern,  southeastern,  southern,  and  southwestern  parts  of  the  state. 
Only  one  of  these,  situated  in  Estill  and  Lee  Counties  and  generally 
known  as  the  Irvine  field,  is  of  very  great  size.  This  includes  a  recent 


L.    C.    GLENN  125 

extension  to  the  southeast  known  as  the  Big  Sinking  Creek  field.  The 
most  northeasterly  are  the  Fallsburg  and  Busseyville  pools  in  Lawrence 
County,  and  the  most  eastern  is  the  Beaver  Creek  field  in  Floyd  County. 
Closely  connected  with  the  Irvine-Big  Sinking  pool  in  the  central  eastern 
part  of  the  state  are  the  Station  Camp,  Lost  Creek,  Campton,  Stillwater, 
and  Cannel  City  pools;  and  a  short  distance  to  the  northeast  is  the 
Ragland  pool.  In  the  southeastern  part  of  the  state  is  the  Knox  County 
area  north  of  B  arbour ville,  and  a  number  of  small  pools  in  Wayne  County. 
In  Lincoln  County,  there  is  a  small  area  northeast  of  Waynesburg.  In 
the  southwest,  there  are  the  Barren  County  fields,  a  small  area  in  the 
eastern  edge  of  Warren  County  and  a  number  of  small  detached  areas 
in  Allen  County,  the  most  important  of  which  are  grouped  about  Scotts- 
ville.  Elsewhere,  there  are  a  few  isolated  wells  or  very  small  groups  of 
wells  not  important  enough  to  be  given  specific  mention. 

The  first  oil  in  Kentucky  was  discovered,  by  accident,  in  1819  while 
drilling  for  a  salt  well  near  the  south  fork  of  Cumberland  River  in 
what  is  now  McCreary  County.  The  oil  came  probably  from  the 
Mississippian.  The  next  find  was  made,  in  1829,  on  Renox  Creek  near 
Burksville,  Cumberland  County,  and  was  from  Ordovician  rocks.  This 
well  flowed  for  many  miles  down  Cumberland  River,  caught  fire,  and 
burned  for  some  time.  Later  its  products  were  used  for  medicinal  and 
other  purposes,  until  about  1860. 

Following  the  discovery  of  oil  in  Pennsylvania,  discoveries  were  made 
in  Wayne  and  other  counties  along  the  Cumberland  river,  from  1861  to 
1866.  Most  of  the  oil  obtained  was  shipped  by  barges  down  the  Cumber- 
land to  Nashville,  although  a  part  was  refined  locally.  Just  after  the 
war,  there  was  renewed  interest  in  the  search  for  oil  and  additional  dis- 
coveries were  made,  especially  in  Allen  and  Barren  Counties,  where  oil 
was  found  close  beneath  the  Devonian  black  shale.  Interest  waned 
between  1870  and  1880,  but  was  revived  during  the  last  two  decades  of 
the  century,  when  additional  discoveries  were  made  in  Barren  County  west 
of  Glasgow,  in  Lawrence  County  on  Big  Blaine  creek,  and  in  Floyd  and 
Knott  Counties  on  the  right  fork  of  Beaver  creek;  while  in  Wayne 
County  renewed  activity  led  to  important  discoveries  in  a  number  of 
localities.  The  most  important  production  in  Wayne  was  found  in  the 
Beaver  sand  in  the  lower  part  of  the  Waverly,  but  some  oil  was  also 
obtained  below  the  black  shale.  During  the  two  decades  from  1880  to 
1900,  the  average  production  for  the  entire  state  was  not  over  5000  bbl. 
per  year;  the  maximum  production  was  in  1899  when  18,280  bbl.  were 
produced. 

The  modern  period  in  the  development  of  oil  in  Kentucky  may  be 
said  to  date  from  the  discovery  of  the  Ragland  field  in  Bath  County,  in 
1900.  In  this  field,  oil  was  found  in  the  Onondaga  limestone  at  a  depth 
of  300  to  380  ft.  (91  to  115  m.)  beneath  the  Licking  River  valley.  By 


126  OIL   FIELDS    OF   KENTUCKY   AND   TENNESSEE 

1904,  the  field  was  practically  drilled  up  and  production  since  then  has 
gradually  declined  until  it  is  very  small.  The  Sunnybrook  pool,  Wayne 
Co.,  was  discovered  in  1901.  Oil  was  obtained  from  the  Trenton,  which 
came  to  be  known  locally  as  the  Sunnybrook  sand.  There  was  a  consider- 
able yield,  but  it  was  short  lived  and  within  a  few  years  the  field  had  been 
abandoned.  Many  further  attempts  have  since  been  made  to  obtain 
oil  from  the  Trenton,  or  Sunnybrook,  both  in  Kentucky  and  in  Tennessee, 
but  so  far  they  have  been  without  success.  Following  the  Sunnybrook 
development,  much  drilling  was  done  elsewhere  in  Wayne  and  adjoining 
counties,  and  a  number  of  small  pools  were  developed,  chiefly  in  the 
Beaver  sand. 

In  1901,  oil  was  found  in  the  northern  part  of  Knox  County  on  Little 
Richland  Creek,  near  Barbourville.  The  oil  came  from  three  sands 
in  the  Pottsville,  named  in  descending  order  the  Wages,  Jones,  and 
Epperson.  The  wells  were  small  producers  and  were  practically  all 
abandoned  in  a  few  years.  Recently  there  has  been  renewed  activity  in 
the  Barbourville  region,  but  nothing  noteworthy  has  developed. 

In  1903,  the  Campton  pool  was  discovered  and  by  1909  had  been 
drilled  up.  Oil  was  found  in  the  Onondaga  limestone.  Many  of  the  wells 
have  since  been  abandoned,  but  others  in  the  field  are  still  pumping 
%  bbl.  or  more  per  day.  Shortly  after  this,  wells  were  gotten  at  Still- 
water  on  the  eastward  continuation  of  the  Campton  structure.  They 
were  very  similar  to  the  Campton  wells  and  have  had  a  similar  history. 
The  same  structure  yielded  oil  at  Cannel  City  in  1912,  and  by  1913  a 
production  of  12,000  bbl.  per  month  had  been  attained.  This  rapidly 
declined,  however,  and  the  production  today  is  merely  nominal. 

For  many  years  oil  has  been  known  near  Irvine,  having  been  originally 
found  in  borings  made  for  salt  wells.  Soon  after  the  discovery  of  oil 
at  Campton  some  shallow  wells  were  bored  at  Ravenna,  near  Irvine,  on 
the  westward  continuation  of  the  structure  on  which  the  Campton  wells 
were  located.  This  structure  is  now  generally  known  as  the  Irvine  struc- 
ture. The  wells  were  very  shallow,  but  yielded  considerable  oil  for  a 
number  of  years,  until  their  decline  led  to  the  removal  of  the  pipe  line 
that  had  been  laid  in  the  early  years  of  their  development,  and  they  were 
entirely  abandoned.  In  1915,  a  well  drilled  3  mi.  northeast  of  Irvine 
started  the  development  of  the  present  Irvine  fields  and  ushered  in  the 
present  period  of  intense  activity  of  oil  development  in  Kentucky.  The 
producing  sand  is  the  Onondaga  limestone,  just  beneath  the  black  shale, 
and  is  generally  known  as  the  Irvine  sand.  The  field  was  rapidly  ex- 
tended eastward  and  by  1917  had  reached  the  Pilot  section  near  Torrent, 
making  the  field  about  12  mi.  long  and  from  1  to  2  mi.  wide.  In  1918, 
there  developed  what  might  be  called  a  southeastward  extension  of  the 
Irvine  field  along  Big  Sinking  Creek.  Development  in  this  new  area 


L.    C.    GLENN 


127 


was  rapid  and  by  the  early  part  of  1919  its  southern  limits  had  been 
reached  a  mile  or  two  northwest  of  Beattyville. 

On  Station  Camp  creek,  some  8  mi.  south  of  Irvine,  a  small  pool  was 
found  in  1916,  at  less  than  100  ft.  (30  m.)  beneath  the  valley  floor.  It 
was  drilled  very  closely  and  was  soon  practically  exhausted.  In  similar 
fashion  another  small,  shallow  pool  was  discovered  and  developed  on 
Ross  Creek.  Decline  has  set  in  there  also  but  exhaustion  has  not  yet 
been  reached.  About  these  two  are  grouped  several  still  smaller  produc- 
tive areas  of  like  character  but  of  still  more  recent  development. 

Meantime,  in  1903,  oil  was  discovered  at  Busseyville  and  Fallsburg, 
Lawrence  Co.,  in  the  Berea  sandstone  about  1400  to  1600  ft.  (426  to  487 
m.)  in  depth.  The  wells  are  small  but  maintain  their  production  for 
years  with  but  slight  decline. 

Although  oil  was  produced  in  Allen  County  about  the  close  of  the  Civil 
War,  it  was  not  until  about  1915  that  the  modern  period  of  production 
there  was  ushered  in  by  the  drilling  near  Scottsville  of  a  number  of  small 
wells  200  to  300  ft.  deep.  The  oil  came  from  close  beneath  the  black 
shale  from  either  Onondaga  or  Niagara  limestone.  Development  has 
been  checked  until  very  recently  by  inadequate  transportation  facilities. 
Most  of  the  development  is  to  the  south  of  Scottsville,  but  there  are 
several  small  areas  in  the  northwestern  part  of  the  county  and  recently 
an  important  well  or  two  have  been  drilled  just  across  the  line  in  the 
eastern  edge  of  Warren  County.  Wildcat  wells  are  being  drilled  in 
numerous  places  in  nearly  all  sections  of  the  state  except  the  central  and 
northern  part,  where  the  surface  rocks  are  of  Ordovician  age,  and  in  the 
extreme  western  part  within  the  area  of  the  Mississippi  embayment 
deposits. 

GEOLOGY  OF  KENTUCKY  OIL  FIELDS 

A  list  of  geological  horizons  designed  to  include  all  sands  that  have  at 
any  time  furnished  oil  in  Kentucky  would  be  quite  lengthy.  A  list  con- 
fined to  horizons  producing  oil  today  in  commercial  quantities  follows: 


PRINCIPAL  PRODUCTIVE  OIL  SANDS  IN  KENTUCKY 


PERIOD 
Carboniferous 


EPOCH 
Pottsville 


Mississippian      Waverly 


OIL  AND  GAS  HORIZONS 
Beaver 

Horton      of  Floyd  and 
Pike        '    KnottCo. 
Salt 
Berea  of  Lawrence  Co. 


Jones         f  of  Knox  Cos. 
Epperson  J 


Devonian 


Onondaga 
(Corniferous) 


Stray  and  1  of  Wayne 
Beaver  }  and  Mc- 
Creek  J  Creary  Cos. 

Of  Olympia,  Ragland,  Cannel  City,  Stillwater, 
Campton,  Irvine,  Big  Sinking  Creek,  Ross  Creek, 
Station  Camp  Creek,  Lanhart,  Buck  Creek, 
Miller's  Creek,  Heidelberg,  Barren  Co.,  Warren 
Co.,  Allen  Co.,  Ohio  Co. 


128  OIL   FIELDS   OF   KENTUCKY   AND   TENNESSEE 

In  Floyd  and  Knott  Counties,  four  sands  occur  in  the  lower  part  of 
the  Pottsville;  these,  in  descending  order,  are:  the  Beaver,  Horton,  Pike, 
and  Salt  sands.  They  are  all  sandstones  and  each  varies  in  thickness 
from  less  than  50  ft.  (15  m.)  to  more  than  300  ft.  (91  m.).  The  interval 
between  them  also  varies  from  a  few  feet  to  over  100  ft.,  making  it  practi- 
cally certain  that  the  sands  split  and  reunite  in  such  irregular  ways  that 
correlation  of  them  is  uncertain.  In  Knox  County,  the  Wages,  Jones, 
and  Epperson  sands  of  the  lower  Pottsville  are  also  sandstones  and  vary 
considerably  both  in  thickness  and  in  interval.  Their  correlation  from 
well  to  well  is  doubtful  at  times  and  no  correlation  has  so  far  been  possible 
with  the  Floyd  County  sands.  The  Berea  sand  of  Lawrence  County  is  a 
medium  grained  sandstone  that  usually  runs  from  50  to  100  ft.  in  thick- 
ness and  lies  at  the  base  of  the  Waverly. 

In  Wayne  and  McCreary  Counties,  the  principal  oil-bearing  horizon 
is  a  cherty,  geodal  limestone  known  as  the  Beaver  Creek  sand.  It  lies 
just  above  the  Chattanooga  black  shale  and  forms  the  basal  member  of 
the  Waverly.  It  varies  greatly  in  thickness,  texture,  and  porosity  and 
the  production  of  the  wells  in  it  varies  accordingly.  In  some  cases,  a 
similar  oil-bearing  limestone  is  found  near  the  top  of  the  Waverly  in  these 
counties  and  is  known  as  the  "Stray  sand."  It  is  usually  from  10  to  30 
ft.  (3  to  9  m.)  thick. 

The  Onondaga,  or  Cornif erous,  limestone  is  by  far  the  most  important 
oil-bearing  horizon  in  the  state.  It  lies  close  beneath  the  Genesee  or 
Chattanooga  black  shale.  It  is  a  soft  brown,  porous  to  cavernous,  mag- 
nesian  limestone  which,  in  the  Irvine  fields,  thickens  to  the  east  from  20 
or  30  ft.  (6  to  9  m.)  about  Irvine  to  from  70  to  95  ft.  on  Big  Sinking  Creek. 
The  pay  exists  in  from  one  to  several  streaks  that  have  no  regular  dis- 
tribution or  position.  Between  the  pay  portions,  the  limestone  is  hard 
and  close  grained.  In  Allen  County,  the  pay  may  extend  down  into 
fissured  or  porous  limestone  of  Silurian  age. 

Genuine  sandstones  occur  in  Kentucky  as  oil-producing  sands  only 
in  the  Pottsville  and  Berea,  and  their  aggregate  production  amounts  to 
less  than  2  per  cent,  of  the  total  production  of  the  state;  98  per  cent,  of 
the  production  comes  from  limestones.  In  a  sandstone,  the  distribution 
of  porosity  is  usually  more  uniform  than  in  a  limestone,  where  the  porous, 
fissured,  or  cavernous  condition  is  apt  to  be  irregular  in  occurrence.  This 
difference  in  the  nature  of  the  two  rocks  explains  the  marked  differences 
in  the  amount  of  pay,  in  the  yield  of  nearby  wells,  and  the  freakish 
occurrence  of  dry  holes  in  the  midst  of  production  where  the  sand  is  a 
limestone. 

If  one  takes  the  percentage  of  the  present  production  from  the  several 
sands  given  in  the  preceding  table,  it  will  become  evident  that  the  pro- 
ducing horizons  in  the  state  vary  greatly  in  their  relative  importance  and 
that  the  one  sand  of  prime  importance  is  the  Onondaga,  or  possibly,  the 


L.    C.   GLENN  129 

Onondaga  linked  with  the  Niagara  for  Ohio  and  parts  of  Barren,  War- 
ren, and  Allen  Counties.  The  aggregate  production,  however,  from  these 
counties  is  so  small,  relatively,  that  the  importance  of  the  Onondaga  as 
the  premier  oil  horizon  of  the  state  is  not  materially  diminished. 

APPROXIMATE  YIELD  OF  OIL  BY  GEOLOGICAL  HORIZONS  IN  KENTUCKY 

PER  CENT. 

Pottsville  of  Knox,  Floyd,  and  Knott  Counties ^  to  1 

Berea  of  Lawrence  County 1 

Stray  and  Beaver  Creek  of  Wayne  and  McCreary  Counties . .  2 

Onondaga,  of  Allen,  Barren,  Warren  and  Ohio  Counties  (?)...  4 

Onondaga,  of  Irvine-Big  Sinking  and  other  nearby  areas 92  to  92>£ 

STRUCTURE  IN  RELATION  TO  OIL  OCCURRENCE 

All  of  the  oil  fields  in  the  central  eastern  part  of  the  state  are  on  the 
eastern  or  southeastern  flank  of  the  Cincinnati  anticline.  The  rocks  in 
which  they  occur  rise  gently  to  the  west  out  of  the  great  Appalachian 
trough,  whose  axis  lies  along  the  extreme  eastern  border  of  the  state. 
Oil  has  migrated  up  the  slope  of  these  rocks  to  the  westward  until  ar- 
rested by  an  anticline  with  a  northeast-south  west  axis,  whose  northwestern 
limb  has  usually  been  faulted  in  simple  or  compound  fashion.  The 
most  important  part  of  the  great  major  anticline  of  this  region  extends 
from  near  Irvine  eastward  to  Paint  Creek,  though  the  extreme  limits  are 
more  remote  at  either  end.  Subordinate  and  somewhat  parallel  anti- 
clines occur  in  the  Ragland  and  in  other  minor  fields  near  the  Irvine  field. 
There  has  apparently  been  some  cross  folding  also  that  has  corrugated 
the  slope  up  which  the  oil  has  migrated  and  concentrated  it  in  certain 
more  favorable  localities.  The  Irvine  field,  however,  presents  certain 
anomalies  worthy  of  mention  in  this  connection.  The  axis  of  the  anti- 
cline pitches  to  the  northeast  at  a  rate  more  than  sufficient  to  cause  the 
migration  of  oil  westward  along  it  and  without,  so  far  as  the  writer  knows, 
any  cross  folding  sufficiently  strong  to  check  such  movement;  yet  oil  is 
found  along  this  axis  at  intervals  from  Irvine  eastward  to  Cannel  City 
with  only  a  few  dry  areas  between  the  separate  pools.  Again,  the  east- 
ern end  of  the  Irvine  field  proper  has  a  broad  southeastward  tongue  that 
extends  a  number  of  miles  down  the  dip  in  the  Big  Sinking  Creek  area. 
It  seems  that  this  oil  should  have  migrated  farther  up  the  slope  to  the 
northwest  and  have  been  found  nearer  the  axis,  since  it  has  salt  water 
below  it  to  push  it  onward. 

In  the  Lawrence  field,  the  Berea  sand  seems  to  have  an  anticlinal 
structure,  which  combined,  perhaps,  with  difference  in  porosity  may 
explain  the  occurrence  of  the  oil  there. 

In  the  Pottsville  sands,  in  Floyd  and  Knott  Counties,  oil  moving  up 
the  dip  to  the  westward  has  been  arrested  either  by  slight  terraces  or  by 

VOL.  LXV. — 9. 


130  OIL   FIELDS   OF   KENTUCKY   AND   TENNESSEE 

encountering  tight  places  in  the  sand.  There  is  no  anticlinal  structure. 
Similar  structural  conditions  prevail,  so  far  as  the  writer  knows,  in  the 
Knox  County  wells  north  of  Barbourville. 

In  the  Wayne  County  field,  the  oil  favors,  according  to  Munn,  the 
sides  and  bottom  of  synclinal  troughs  that  slope  gently  eastward. 

In  Allen  County,  recently  published  work  by  Shaw  and  Mather  show 
a  number  of  small  anticlines  and  domes  with  an  area  of  2  to  3  sq.  mi. 
each,  superimposed  upon  a  prevalent  northwestward  dip  of  perhaps  40  ft. 
(12  m.)  to  the  mile.  These  have  a  closure  of  25  to  30  ft.  (7  to  9  m.)  or 
less,  and  their  location,  from  a  study  of  the  surface,  is  often  difficult  or 
impossible  because  of  lack  of  exposures.  These  same  features  and  lack 
of  exposures  characterize  much  of  Barren  County  and  the  eastern  part  of 
Warren  County.  In  the  western  part  of  Warren  County,  exposures  are 
better  and  pronounced  doming  and  terracing  occurs.  These  structures 
have  yielded  considerable  shows  of  oil  near  Gasper  River. 

Water  usually  follows  the  oil  in  the  Onondaga  rather  closely.  It 
soon  begins  showing  in  the  wells  in  the  lowest  part  of  the  structure  and, 
as  time  passes,  invades  the  field  farther  and  farther  up  the  dip.  Water 
has  thus  encroached  upon  part  of  the  Irvine  field  and  has  appeared  in 
the  Big  Sinking  field.  Concerted  efforts  should  be  taken  by  operators 
there  to  combat  this  invasion. 

TECHNOLOGY 

Drilling  was  formerly  by  standard  rig;  and  in  deep  tests  in  wildcat 
territory  this  method  is  still  used.  Most  of  the  known  production  can, 
however,  more  easily  be  reached  by  drilling  machines.  Wells  in  the  Allen 
fields  250  to  300  ft.  (76  to  91  m.)  deep  cost  about  $1000  complete.  In 
the  Big  Sinking  field,  wells  800  to  900  ft.  deep  cost  about  $3500;  while 
those  1000  to  1200  ft.  deep  cost  from  $5000  to  $6000.  Prices  for  drilling 
tend  to  rise  in  harmony  with  all  other  prices  at  present. 

The  size  of  Kentucky  wells  varies  greatly  both  for  the  various  pools 
and  for  adjacent  locations  in  the  same  pool.  This  is  true  especially  if 
the  sand  is  a  limestone.  The  rate  of  decrease  also  varies  greatly.  Re- 
liable determinations  of  this  rate  are  made  difficult  by  the  development 
of  the  more  important  pools  having  been  so  recent  that  their  records  of 
production  extend  over  only  a  very  few  years.  This  difficulty  is  further 
increased  by  the  fact  that  pipe-line  facilities  have  until  very  recently  been 
entirely  inadequate  to  take  care  of  the  production.  In  the  Allen  County 
fields,  transportation  conditions  have  been  especially  bad,  and  while 
partly  remedied  are  not  yet  entirely  satisfactory. 

In  Lawrence  County,  wells  in  the  Berea  sandstone  come  in  at  from 
4  to  8  or  10  bbl.  and  show  only  a  very  slow  decline  over  a  long  period 
of  years. 

In  Floyd  County,  where  the  oil  is  also  derived  from  sandstone,  the 


L.    C.    GLENN  131 

initial  production  is  likewise  small  but  is  well  maintained.  Some  of  the 
wells  drilled  10  to  20  years  ago  show  only  slight  decline. 

In  Wayne  County,  where  production  is  from  a  limestone,  the  initial 
yield  varies  greatly,  though  some  of  the  largest  wells  produced  from  100 
to  500  bbl.  daily  for  a  short  time.  The  average  initial  production,  how- 
ever, is  well  below  100  bbl.  These  wells  soon  settle  to  20  bbl.  or  less  per 
day  and  then  usually  show  only  a  slight  further  decline.  In  some 
cases  there  has  been  practically  no  decline  in  15  years;  in  other  cases,  the 
yield  in  that  time  has  decreased  to  a  barrel  or  two  or  even  less.  Many 
of  these  old  wells  have  been  overhauled  recently  and  put  on  a  vacuum 
with  a  gratifying  increase  in  yield. 

In  the  Irvine  district,  initial  production  also  varies  greatly.  The 
average,  given  by  Shaw,  for  successful  wells  drilled  between  October, 
1915,  and  February,  1917,  is  about  39  bbl.,  and  the  producing  wells  were 
89  per  cent,  of  the  total  number  drilled.  Few  exceeded  100  bbl.  each. 
In  Big  Sinking  Creek  a  number  of  wells  have  had  an  initial  production 
of  several  hundred  barrels  and  a  few  have  probably  yielded  1000  bbl. 
per  day.  The  decline  in  the  Irvine  field  by  the  end  of  the  first  year  has 
been  to  about  10  per  cent,  of  the  initial  yield,  although  some  wells  have 
held  up  considerably  better.  This  rate  of  decline  has  been  due  to  the 
porosity  of  the  sand  and  the  close  spacing  of  the  wells  in  many  cases. 
In  parts  of  the  Station  Camp  and  Ross  Creek  pools,  wells  have  been 
spaced  one  to  an  acre  or  less.  The  well  spacing  in  the  Big  Sinking  field 
has  also  been  entirely  too  close  on  certain  properties  and  has  been  at- 
tended with  a  rapid  decrease  in  production. 

In  the  Allen  County  region,  about  75  per  cent,  of  the  wells  drilled 
have  been  successful.  Initial  production  for  the  larger  wells  has  varied 
from  25  to  100  bbl.  per  day  with  a  few  exceptional  wells  yielding  200  to 
300  bbl.  The  gas  pressure  behind  these  largest  wells,  however,  is  quickly 
relieved  and  in  a  few  days  they  decrease  greatly.  By  the  end  of  the  first 
month,  the  larger  ones  yield  from  one-fourth  to  one-third  of  their  initial 
production,  while  the  smaller  ones  hold  up  somewhat  better.  These 
smaller  wells  come  in  at  from  5  to  20  bbl.  per  day. 

In  Barren  County,  a  well  recently  abandoned  because  of  decreased 
flow  and  the  eating  away  of  the  casing  produced  oil  for  over  40  years  and 
during  that  period  showed  a  remarkably  low  decline  curve.  It  was  prob- 
ably next  to  the  oldest  well  in  the  country  at  the  time  of  abandonment.1 

Future  production  curves  and  tables  have  been  published  by  the 
Internal  Revenue  Department  for  Floyd  County,  Beaver  Creek  in  Wayne 
County,  Ragland  and  Irvine,  in  its  "Manual  for  the  Oil  and  Gas  Industry. " 

The  oil  varies  considerably  in  character.  Most  of  it  is  dark  green 
by  reflected  light,  but  dark  brown  when  seen  by  transmitted  light  in  thin 
films.  A  little  amber  oil  has  been  reported  from  Barren,  and  occasion- 

1  A  well  in  Wirt  County,  W.  Va.,  drilled  in  1860  is  still  producing. 


132  OIL  FIELDS  OP  KENTUCKY  AND  TENNESSEE 

ally  elsewhere,  but  the  quantity  of  such  oil  is  negligible.  In  gravity, 
it  ranges  from  26°  to  45°  Be".  In  the  Floyd  field,  the  average  is  about  40°. 
In  Wayne  county,  it  varies  from  36°  to  43°.  In  the  Irvine  field,  the 
average  range  is  30°  to  36°.  In  the  Ragland  field,  the  average  is  26° 
or  27°.  Allen  county  averages  from  35°  to  38°;  and  Barren  about 
40°  to  42°.  The  gasoline  content  is  usually  high. 

In  the  Lawrence,  Floyd,  Knox,  and  Wayne  County  fields,  no  ab- 
normal values  have  attached  to  lands;  but  in  the  Irvine  district  values,  es- 
pecially in  Big  Sinking  field,  have  rapidly  risen  until  prices  of  $2000  to 
$5000  per  acre  have  been  reached  with  extra  royalties  at  times.  In 
Allen  County  and  near  the  Moulder  well  in  the  eastern  part  of  Warren 
County,  high  prices  have  also  been  given  recently  for  acreage.  Wildcat 
acreage  has,  in  many  places,  been  held  at  high  figures  when  compared 
with  equal  grade  acreage  in  many  other  states  and  much  develop- 
ment in  certain  sections  has  been  retarded  by  these  prices. 

The  great  bulk  of  the  oil  in  Kentucky  is  transported  by  the  Cumber- 
land pipe  line,  which  has  lines  serving  practically  all  of  the  eastern  and 
southeastern  parts  of  the  state.  It  does  not,  however,  reach  the  fields  of 
Allen  and  adjacent  counties.  Until  recently  its  capacity  was  inadequate 
to  care  for  the  possible  full  production.  A  little  oil  in  the  eastern  fields 
is  handled  by  short  private  lines,  by  barges,  or  by  tank  cars.  In  Allen 
County,  several  small  pipe  lines  gather  the  oil  and  deliver  it  to  loading 
racks  at  Scottsville  and  Bowling  Green  for  shipment  to  Nashville,  Louis- 
ville or  elsewhere. 

FUTURE  POSSIBILITIES 

There  is  a  good  chance  for  finding  a  number  of  small  pools  in  the  Potts- 
ville  and  the  Berea  in  the  eastern  part  of  the  state  on  small  structures  or 
under  favorable  conditions  of  the  sand.  Such  pools  may  be  expected  to 
have  the  general  character  of  those  in  Lawrence,  Floyd,  and  Knox 
Counties,  starting  with  a  small  production,  but  sustaining  it  well  for  a 
long  period.  • 

The  Onondaga  oil  is  seemingly  confined  to  a  narrow  belt  near  the 
outcrop  of  these  rocks  in  the  central  eastern  part  of  the  state,  which 
has  already  been  pretty  thoroughly  tested  and  developed.  The  writer 
looks  for  no  large  new  pool  from  that  horizon  there.  Where  the  Onon- 
daga crosses  the  saddle  between  the  Cincinnati  and  Nashville  domes  in 
the  Barren,  Warren,  and  Allen  areas,  there  doubtless  remain  a  number 
of  new  finds;  but  the  difficulty  in  determining  the  structure  because  of 
the  prevalent  surface  soil  covering  will  make  their  discovery  either  a 
matter  of  slow  detailed  work  or  of  chance. 

There  should  be  chances  of  finding  oil  on  the  sides  of  the  basin  in  which 
the  west  Kentucky  coal  field  lies  where  the  Mississippian,  Devonian,  and 
perhaps  Silurian  rocks  rise  from  that  basin  to  the  east  and  southeast, 


DISCUSSION  133 

wherever  domes,  terraces,  or  other  favorable  structures  can  be  located. 
The  chance  on  the  south  side  of  this  basin  is  less  favorable  because  of 
the  extensive  faulting  there. 

Within  the  West  Kentucky  coal  field,  the  writer  believes  the  only 
favorable  chance  of  finding  oil  is  along  the  Gold  Hill-Rough  Creek  dis- 
turbance and  conditions  there  are  complicated  because  of  the  severity 
of  the  folding  and  faulting.  In  the  Gulf  embayment  deposits  of  West 
Kentucky,  there  are  no  known  structures;  and  it  is  too  soon  to  make 
prediction  worth  anything  until  the  results  of  the  testing  soon  to  be  done 
in  the  nearby  Reelfoot  Lake  district  in  Tennessee  are  known.  Much 
light  should  then  be  thrown  on  the  oil  possibilities  of  these  embayment 
rocks  in  Kentucky. 

Little  or  no  oil  need  be  expected  in  the  Ordovician  or  in  any  older 
rocks  and  drilling  in  any  part  of  the  central  blue  grass  limestone  region 
of  the  state  is  practically  money  wasted. 

DISCUSSION 

MORTIMER  A.  SEARS,  Huntington,  W.  Va.  (written  discussion). — In 
dealing  with  the  future  possibilities  for  oil  and  gas  in  Kentucky,  I  regret 
that  Doctor  Glenn  has  failed  to  mention  the  Paint  Creek  Dome,  which 
lies  in  parts  of  four  counties,  viz.,  Johnson,  Magoffin,  Morgan,  and  Law- 
rence. This  immense  structural  uplift  has  possibilities  second  to  none 
in  the  state.  It  lies  along  the  line  of  structural  uplift  known  to  extend 
from  the  Irvine  field  through  Kentucky,  and  into  West  Virginia,  where 
it  is  known  as  the  Warfield  anticline. 

In  an  article  that  I  wrote  for  the  Oil  and  Gas  Journal  (May  21,  1917), 
I  stated  the  geologic  facts  in  connection  with  this  field,  which  at  that  time 
was  strictly  a  wildcat  proposition.  It  is  true  that  wells  have  been  put 
down  at  various  times  since  about  1860,  but  such  operations  were  spas- 
modic and  haphazard.  So  far  as  I  know  there  had  been  no  geologic 
report  relating  to  oil  and  gas  upon  this  area  at  the  time  I  made  my  exami- 
nation (February,  1917) — except  in  the  form  of  a  communication  from 
Prof.  J.  P.  Leslie  to  the  American  Philosophical  Society  in  1865.  After 
February,  1917,  development  dragged  along  slowly  until  about  a  year 
ago,  when  more  energetic  measures  were  inaugurated,  with  the  result 
that  about  20,000,000  cu.  ft.  of  gas  per  day  has  been  developed  and 
several  oil  wells  having  capacities  of  from  3  to  50  bbl.  per  day  have  been 
brought  in. 

Commercial  quantities  of  gas  occur  in  the  Weir  sand  at  a  depth  from 
the  surface  of  about  850  ft.  (259  m.) ;  it  varies  in  thickness  from  20  to 
40  feet.  Part  of  the  product  is  sold  to  the  Central  Kentucky  Natural 
Gas  Co.,  and  part  to  the  Louisville  Gas  and  Electric  Co.  These  two  com- 
panies have  main  gas  lines  extending  through  the  field  about  5  mi.  from 


134  OIL   FIELDS    OF   KENTUCKY   AND    TENNESSEE 

the  particular  area  in  which  gas  has  been  found.  Lateral  lines  have 
been  laid  and  compressor  plants  are  in  operation. 

The  largest  oil  wells  in  the  field  find  their  product  in  the  Weir  sand 
also,  although  commercial  quantities  of  oil  have  been  found  in  the  Berea. 
The  Weir  sand  appears  to  be  a l 'genuine  sandstone"  and  seems  to  prove 
an  exception  to  Doctor  Glenn's  statement  that  genuine  sandstones  occur 
in  Kentucky  as  oil-producing  sands  only  in  the  Pottsville  and  Berea. 
It  may  correspond  to  one  of  the  oil  sands  of  Wayne  and  McCreary 
Counties,  but  it  certainly  cannot  be  called  a  "geodal  limestone." 

The  Keener,  also,  has  produced  small  amounts  of  oil.  It  is  from  this 
sand  that  a  well  recently  brought  in  produced  an  oil  of  51°  Be*,  gravity. 
The  weir  oil  runs  about  38°  Be*.  The  Cumberland  Pipe  Line  Co.  expects 
soon  to  lay  a  line  into  the  field. 

The  last  well  brought  in  showed  the  Weir  sand  to  be  over  60  ft. 
(18  m.)  thick  with  a  16-in.  (40-cm.)  break.  Thus  far,  wells  drilled  to 
the  Onondaga  (Coniferous)  have  proved  disappointing  and  no  pro- 
duction has  been  found  in  the  Clinton.  Comparatively  few  wells  are 
drilled  below  the  Weir  so  that  it  is  yet  too  early  to  condemn  the  lower 
formations. 

Leases  are  constantly,  changing  hands.  Very  little  acreage  remains 
in  the  hands  of  the  land  owner.  Whenever  a  well  is  brought  in,  leases 
sold  on  adjacent  property  bring  from  $100  to  $150  per  acre.  With  the 
opening  of  spring  there  is  no  question  but  that  this  area  will  be  the  scene 
of  the  greatest  activity  in  the  state  of  Kentucky. 

WILBUR  A.  N.  NELSON,*  Nashville,  Tenn.  (written  discussion). — 
Certain  pertinent  facts  in  regard  to  the  oil  produced  in  Tennessee  in  the 
past  and  to  the  extension  of  the  different  formations  of  Allen  County, 
Kentucky,  into  Middle  Tennessee  are  not  given  in  this  paper. 

The  very  heavy  slump  in  production  that  occurred  in  the  old  Riverton 
Spurrier  district  of  Pickett,  Tenn.,  was  due  to  fresh- water  troubles. 
A  recent  study  of  the  water  troubles  of  this  field  brings  out  these  facts: 
Under  the  Chattanooga  " black"  shale  occurs  a  practically  uniform  bed 
of  Ordovician  limestone,  bedded  or  creviced  so  as  to  permit  a  connection 
between  the  different  gas  shows  in  the  upper  part  of  the  limestone 
immediately  under  the  black  shale  and  the  oil  horizons  in  the  base  of  the 
limestone,  some  165  to  270  ft.  below  the  black  shale.  In  the  old  wells, 
the  casing  was  set  below  the  gas  shows  and  just  above  the  oil  horizon. 
That  the  release  of  the  gas  pressure  permitted  the  fresh  water  to  flow 
down  through  the  limestone  joints,  bedding  planes,  or  fractures  to  the 
oil  horizon  and  thus  drown  out  the  well,  seems  to  have  been  proved  by 
Mr.  J.  H.  Compton,  of  Riverton.  Several  years  ago  he  reset  the  casing 
in  one  well  above  the  first  gas  show  and,  after  plugging  the  other  wells, 

*  State  Geologist,  Tennessee  Geological  Survey. 


DISCUSSION  135 

above  the  gas  horizon,  started  pumping.  After  several  weeks,  the  well 
again  commenced  to  produce  oil. 

A  structural  report  recently  made  on  this  area  by  the  Tennessee 
Geological  Survey,  in  cooperation  with  the  U.  S.  Geological  Survey, 
shows  that  the  best  old  producing  wells  were  located  on  the  crest  and 
north  flank  of  a  long  narrow  anticline  extending  in  a  direction  of  approxi- 
mately north  60°  east  and  that  the  oil  probably  occurs  in  pools  of  small 
extent  with  a  radius  of  about  J^  mi.  Several  similar  anticlines  were 
mapped  in  this  district,  which  are  yet  untested.  The  Cumberland  Pipe 
Line  Co.  laid  a  2-in.  line  into  this  field  in  1902,  which  was  removed  in 
1905,  due  to  a  decline  in  oil  production  but  primarily  to  the  levying  of  a 
$10,000  annual  tax  on  the  line  by  Pickett  County.  During  this  time 
58,776  bbl.  of  oil  were  piped  from  this  field,  of  which  over  36,000  bbl. 
came  from  one  well,  known  as  the  Bobs  Bar  well,  which  shortly  went  to 
water. 

In  Sumner  County,  Tenn.,  and  in  adjoining  counties  to  the  west  and 
southwest  on  the  Highland  Rim,  there  is  at  present  much  drilling  going 
on,  but  the  majority  of  these  wells  have  been  drilled  without  paying  any 
attention  to  structure.  This  was  recently  shown  in  Sumner  County, 
which  joins  Allen  County,  Ky.,  on  the  south.  A  detailed  structural  map 
of  part  of  this  county  made  by  the  Tennessee  Geological  Survey,  in 
cooperation  with  the  U.  S.  Geological  Survey,  shows  that  of  over  30 
holes  drilled  only  two  were  located  on  favorable  structure.  But  on  that 
particular  dome,  one  could  have  little  hope  of  finding  oil,  as  the  oil  horizon 
had  been  cut  through  on  the  south  flank  of  the  dome.  The  structurally 
favorable  places  are  still  untested. 

In  Allen  County,  Ky.,  around  Scottsville,  the  oil  is  found  at  three  hori- 
zons below  the  Chattanooga  black  shale.  These  three  sands  are  not 
always  present  at  one  place;  and  when  present,  as  a  rule  only  one  is 
producing.  The  upper,  sometimes  the  two  upper,  sands  are  considered 
of  Devonian  ^ge  and  probably  correlate,  in  Tennessee,  with  the  Pegram 
limestone.  The  lower  sand,  which  produces  most  of  the  oil  to  the  south 
of  Scottsville,  is  thought  to  be  of  Silurian  age  and  to  be  Louisville  limestone, 
as  this  formation  outcrops  in  Sumner  County,  Tenn.,  just  south  of  Allen 
County,  Ky.,  at  the  base  of  the  Chattanooga  black  shale,  the  Corniferous 
beds  of  Devonian  age  being  absent. 

The  location  of  the  old  shore  line  of  the  Pegram  limestone,  as  it  is 
known  in  Tennessee,  and  of  the  Corniferous  limestone,  as  it  is  known  in 
Kentucky,  is  important.  Exposures  of  this  limestone  are  not  known 
south  of  Petroleum,  Allen  County,  Ky.  No  outcrops  are  known  in 
Sumner  County,  Tenn.,  but  it  appears  again  12  mi.  (19  km.)  west  of 
Nashville,  at  Newsom  Station,  where  it  has  a  thickness  of  3  ft.  (0.9  m.) ; 
a  few  miles  farther  west,  at  Pegram,  in  Cheatham  County,  it  has  a  thick- 
ness of  12  ft.  From  these  exposures  it  would  appear  that  this  shore 


136  OIL  FIELDS   OF  KENTUCKY  AND   TENNESSEE 

line  would  extend  from  Newsom  Station  northeastward  through  Cheat- 
ham  and  Robertson  Counties,  Tenn.,  probably  passing  in  the  vicinity 
of  Springfield,  and  crossing  the  state  line  in  the  proximity  of  the  north- 
east corner  of  Robertson  County,  near  Mitchellville.     All  territory  as 
far  west  of  this  area  as  the  Tennessee  River  is  underlain  by  Devonian 
limestones.    A  well  was  brought  in,  in  January,  1920,  in  Simpson  County, 
Ky.,  about  3  mi.  from  the  northeast  corner  of  Robertson  County,  Tenn. 
in  a  very  peculiar  sandy  limestone  61  ft.  below  the  Chattanooga  black 
shale.    The  sand  was  penetrated  to  a  depth  of  7  ft.  and  may  be  a 
phase  of  the  Harriman  chert  of  Oriskany  age,  which  outcrops  about 
50  mi.  to  the  southwest  near  Cumberland  City,  Stewart  County,  Tenn. 
The  shore  line  of  the  other  supposedly  oil-bearing  limestone,  the 
Louisville  limestone  of  Silurian  age,  is  of  interest  because  of  the  effect 
it  would  have  on  possible  oil  territory  in  the  counties  on  the  western 
Highland  Rim  of  Tennessee.    In  Sumner  County  south  of  Westmoreland, 
it  is  20  ft.  thick,  while  about  25  mi.  to  the  southwest  near  Ridgetop,  in 
Robertson  County,  it  only  shows  a  thickness  of  10  ft.     Farther  to  the 
southwest,  in  southern  Cheatham  County  around  Pegram,  it  is  very 
thin,  having  a  15  ft.  exposure.    On  the  western  edge  of  the  Highland 
Rim  along  the  Tennessee  River,  this  formation  changes  to  a  shaly  phase, 
known  as  the  Lobelville,  which  varies  in  thickness  from  1 0  to  75  ft.    These 
facts  would  indicate  that  the  extent  of  the  limestone  phase  of  the  Louis- 
ville formation  would  lie  just  to  the  southeast  of  the  present  edge  of  the 
Highland  Rim  on  the  Middle  Basin  of  Tennessee,  as  far  south  as  Pegram, 
and  that  at  this  point  the  line  would  turn  to  the  northwest,  swinging  back 
into  Kentucky.    The  extreme  thinness  of  the  formation,  except  in  the 
northern  part  of  Sumner  County  and  probably  in  the  northern  part  of 
Robertson  County,  would  indicate  that  only  in  these  two  areas  would 
it  be  thick  enough  to  act  as  a  commercial  oil  reservoir.     The  long  narrow 
embayments  in  which  this  and  the  overlying  formations  were  laid  down 
make   it    probable   that  there  are  areas  in  the  northern   Highland 
Rim  counties  lying  outside  of  these  old  embayment  areas  in  which  these 
formations  were  never  deposited.     In  the  more  southern  counties  on  the 
Highland  Rim  west  of  Nashville,  overlapping  formations  come  in  between 
the  Louisville  limestone  and  the  Chattanooga  black  shale,  which  would 
keep  this  formation  from  containing  oil  if  such  oil  is  derived  from 
the  Chattanooga  black  shale.    That  this  formation  is  probably  absent 
in  the  southwestern  part  of  Robertson  County  is  indicated  by  the  fact 
that  a  recent  well  on  Sulphur  Fork,  6  mi.  southwest  of  Cedar  Hill,  which 
went  to  a  depth  of  1015  ft.  and  passed  through  the  Chattanooga  black 
shale  at  615  ft.,  encountered  no  water,  oil,  or  gas  below  the  Chattanooga. 
This  hole  probably  passed  through  the  rocks  of  Trenton  age  at  950  ft. 
The  presence  of  blue  phosphate  sand  in  the  limestone  above  this  level 
is  taken  as  evidence  of  the  presence  of  the  Hermitage  formation  of  Tren- 
ton age  at  this  depth. 


DISCUSSION  137 

In  western  Tennessee,  two  deep  tests  are  being'drilled,  one  in  Lake 
County  at  Proctor  City  on  the  west  side  of  Reelfoot  Lake  and  the  other 
in  Obion  County  near  Walnut  Log  on  the  northeast  side  of  Reelfoot  Lake. 
From  numerous  exposures  of  the  formations  just  under  the  loess  bluffs 
northeast  of  Reelfoot  Lake,  it  is  thought  that  there  is  a  marked  anti- 
clinal area  just  to  the  northeast  of  Walnut  Log  and  extending  over  the 
Tennessee  state  line  into  Kentucky.  The  oil  and  gas  rights  on  Reel- 
foot  Lake,  which  belongs  to  the  state  of  Tennessee,  have  been  leased 
by  the  Governor  to  the  men  who  are  drilling  near  Walnut  Log.  This 
hole  is  on  land  joining  the  state  property.  Among  other  things  the  state 
requires  that  the  well  be  drilled  to  a  depth  of  3000  ft.  The  Paleozoic 
floor  of  the  gulf  embayment  should  be  reached  inside  of  that  distance, 
while  the  formations  producing  oil  in  the  northwest  corner  of  Louisiana 
should  be  reached  at  about  2200  ft. 

In  Allen  County,  Ky.,  detailed  structural  work  done  to  the  south  of 
Scottsville  shows  that  in  the  area  thus  mapped  the  best  production  comes 
from  the  northwest  or  west  side  of  small  structural  domes,  with  closures 
of  about  20  ft.,  but  where  the  dome  has  a  very  steep  dip  on  the  north  or 
northwest  side,  with  gentle  dips  to  the  south,  the  production  is  obtained 
on  the  south  and  southwest  sides.  Such  production  is  always  less  than 
the  production  from  the  northwest  sides  of  Allen  County  domes.  In 
small  wells  that  are  shot,  the  production  often  drops  off  four-fifths  after 
the  first  two  or  three  days.  In  several  cases,  wells  that  have  come  in 
producing  salt  water  change  to  oil  after  about  two  weeks  pumping,  and 
make  average  producers.  No  fresh  water  is  encountered  in  the  Allen 
County  wells  below  the  Chattanooga  black  shale.  The  average  produc- 
tion in  this  section  is  probably  not  more  than  5  bbl.  per  pumping  well. 

STUAKT  ST.  CLAIR,  Bowling  Green,  Ky.  (written  discussion). — 
Doctor  Glenn's  paper  is  interesting  as  an  historical  resum£  of  the  oil  de- 
velopment in  these  states,  the  former  of  which  has  come  into  prominence 
during  the  past  few  years,  producing,  in  1919,  approximately  8,000,000 
bbl.  of  high-grade  oil. 

The  writer  had  hoped  that  Doctor  Glenn  would  give  more  detailed 
data  on  the  accumulation  of  oil  in  the  Onondaga  limestone,  as  that  forma- 
tion furnishes  about  96  per  cent,  of  the  oil  production  of  Kentucky.  If 
he  had,  in  his  discussion  of  the  eastern  part  of  the  state,  he  would  have 
noticed  that  his  statement  that  oil  has  migrated  westward  up  the  slope 
of  the  rocks  which  rise  from  the  great  Appalachian  trough  until  arrested 
by  an  anticline  with  a  northeast-southeast  axis,  would  need  some  modifica- 
tion or  further  explanation.  Between  the  Appalachian  trough  and  the 
Irvine  District,  the  latter  comprising  the  oil  fields  of  Lee,  Estill,  Powell, 
and  Wolfe  Counties,  there  are  a  number  of  well-defined  anticlinal  struc- 
tures that  have  been  drilled  upon  with  unsuccessful  results.  The  Onon- 
daga formation  does  not  have  a  continuous  bed  of  such  porosity  as  would 


138  OIL   FIELDS    OF   KENTUCKY   AND    TENNESSEE 

be  needed  for  migration  of  oil,  except  within  a  restricted  distance  from 
its  outcrop  and  from  the  Irvine  fault.  Therefore,  migration  of  oil  in 
this  formation  took  place  only  over  a  short  distance.  As  explained 
by  the  writer  in  a  paper2  on  the  Irvine  Oil  District,  the  greater  part  of 
the  porosity  in  certain  beds  of  the  Onondaga  from  which  oil  is  produced 
is  caused  by  solution  by  circulating  meteoric  water  which  has  entered  at 
the  outcrop  and  along  fault  planes.  It  is  this  theory  that  explains  the 
position  and  structural  relations  of  the  prolific  Big  Sinking  Creek  pool 
of  Lee  County. 

In  view  of  what  has  been  said,  Doctor  Glenn's  statement  that  water 
usually  follows  the  oil  in  the  Onondaga  rather  closely  may  need  partial 
revision.  It  is  true  that  wherever  there  is  oil  in  commercial  quantities 
there  is  also  water,  for  water  has  in  most  cases  caused  the  porosity  in  the 
rock  in  which  the  oil  has  accumulated.  However,  there  are  areas  where 
there  are  very  small  wells  of  doubtful  commercial  value,  the  oil  having 
accumulated  in  the  Onondaga  where  there  may  have  been  a  little  porosity 
induced  by  recrystallization  or  partial  dolomitization,  where  there  is  a 
total  absence  of  water.  Outside  of  a  restricted  distance  from  the  outcrop 
of  the  Onondaga  or  from  major  faults,  wells  drilled  on  anticlines  or  in 
synclines  show  a  general  absence  of  both  oil  and  water. 

How  far  the  thought  developed  by  the  writer,  in  his  paper  men- 
tioned above,  showing  the  relation  between  the  area  affected  by 
circulation  of  meteoric  water  and  oil  accumulation  in  the  Onondaga 
limestone  in  Kentucky  can  be  applied  to  other  fields  where  the  oil  pro- 
duction is  from  a  porous  limestone,  cannot  be  stated,  but  he  hoped  that 
the  idea  advanced  might  be  used  with  additions  or  modifications  in 
helping  to  explain  accumulation  problems  in  other  limestone  fields. 

Two  minor  corrections  should  be  made  in  Doctor  Glenn's  paper  for 
the  benefit  of  those  unfamiliar  with  the  Kentucky  fields.  First,  the 
gravity  of  the  oil  for  the  Irvine  field  is  given  correctly  but  it  should  not 
be  thought  to  include  the  adjacent  Big  Sinking  field.  In  the  latter  the 
gravity  is  much  higher,  running  from  38°  to  42°  Be.  and  the  gasoline 
content  is  exceptionally  high.  Second,  the  great  bulk  of  the  oil  in 
Kentucky  is  not  carried  by  the  Cumberland  Pipe  Line  Co.  at  the  present 
time.  In  the  fields  of  Lee  and  adjacent  counties,  the  Cumberland  runs 
but  little  more  than  half  the  production;  the  balance  is  handled  by  six 
other  pipe  line  companies,  chief  among  which  are  the  Indian  Refining, 
Great  Northern,  and  National  Refining.  In  Allen  County,  the  Indian 
Refining  handles  nearly  all  the  production,  although  recently  two  other 
pipe  lines  have  entered  the  field. 

The  writer  fully  agrees  with  Doctor  Glenn  in  his  outline  of  the  areas 
of  Kentucky  that  contain  possibilities  for  future  production.  In  his 


2  See  p.  165. 


DISCUSSION  139 

opinion,  even  the  Allen,  Barren,  and  Warren  County  areas  are  about 
outlined  at  the  present  time.  In  the  western  Kentucky  coal  field,  de- 
velopment will  be  slow,  but  something  of  importance  may  be  opened  in 
the  Chester  or  lower  Mississippian  sands.  Kentucky  cannot  hope  for  a 
second  Big  Sinking,  which  is  the  most  important  field  in  the  history  of 
oil  production  in  the  state.  The  flush  was  taken  from  this  pool  in  1919 
and  the  production  for  that  year  will  mark  the  apex  of  the  production 
curve  for  the  state.  The  decline  in  the  curve  will  not  be  great  for  1920, 
but  after  this  year  the  decline  will  be  noticeable. 

In  Tennessee,  aside  from  a  probable  few  small  pools  along  the  High- 
land Rim  in  the  limestone  underlying  the  Chattanooga  black  shale  and 
within  a  restricted  distance  from  the  outcrop  of  this  limestone  formation, 
or  from  a  major  fault,  and  a  possible  few  small  pools  in  the  coal-measure 
area  in  the  eastern  part  of  the  state,  the  oil  possibilities,  in  the  writer's 
opinion,  lie  in  certain  areas  within  the  Gulf  Embayment  province  west 
of  Tennessee  River. 


140  OIL   POSSIBILITIES   IN  NORTHERN   ALABAMA 


Oil  Possibilities  in  Northern  Alabama 

BY  DOUGLAS  R.  SEMMBS,*  PH.  D.,  UNIVERSITY,  ALA. 

(Lake  Superior  Meeting,  August,  1920) 

THE  possible  oil  territory  of  Alabama  can  be  readily  divided  into 
two  regions,  the  Paleozoic  area  of  the  north,  and  the  Coastal  Plain 
province  of  Cretaceous  and  younger  formations  lying  to  the  south. 
This  latter  area  has  received  much  attention  in  the  last  few  years  and 
has  been  described  by  a  number  of  writers.1  Although  the  possibilities 
of  the  Cretaceous  series  have  been  much  emphasized  by  recent  writers, 
the  fact  remains  that  the  two,  or  possibly  three,  localities  where  oil  or 
gas  have  been  found  in  anything  like  paying  quantities  are  confined 
to  the  area  of  Carboniferous  rocks.  Moreover,  almost  all  of  the  oil 
seeps  and  a  good  percentage  of  the  gas  seeps  are  confined  to  this  area.2 

Topographically,  as  well  as  structurally,  the  Paleozoic  area  can  be  di- 
vided into  three  rather  well  defined  provinces:  (1)  The  broad,  open 
Coosa  Valley  lying  adjacent  to  the  crystalline  oldland,  with  compara- 
tively little  relief,  except  for  occasional  longitudinal  ridges  and  rather 
intense  folding;  (2)  the  plateau  region  of  horizontal  or  gently  warped 
Pennsylvanian  strata  broken  by  occasional  anticlinal  valleys  aligned 
northeast  and  southwest,  outliers  of  the  Coosa  Valley  proper,  in  which 
the  older  Paleozoic  formations  are  exposed — a  region  of  much  relief  (200 


*  Associate  Professor  of  Geology,  University  of  Alabama. 

Eugene  A.  Smith:  Report  on  the  Geology  of  the  Coastal  Plain  of  Alabama. 
Geol.  Survey  of  Alabama  (1894). 

Eugene  A.  Smith:  Concerning  Oil  and  Gas  in  Alabama.     Circular  3,   Geol. 
Survey  of  Alabama  (1917). 

O.  B.  Hopkins:  Oil  and  Gas  Possibilities  of  the  Hatchetigbee  Anticline,  Alabama. 
U.  S.  Geol.  Survey  Bull  661  (1917)  281. 

Dorsey  Hager:  Possible  Oil  and  Gas  Fields  of  the  Cretaceous  Beds  of  Alabama. 
Trans.  (1918)  59,  424. 

J Among  the  more  important  references  on  northern  Alabama  are: 

Henry  McCalley:  Report  on  the  Valley  Regions  of  Alabama.     Part  I.     (Ten- 
nessee Valley.)     Geol.  Survey  of  Alabama  (1896). 

M.  3.  Munn:  Reconnaissance  Report  on  the  Fayette  Gas  Field,  Alabama.     Geol. 
Survey  of  Alabama  Bull.  10  (1911). 

jEugene  A.  Smith:  Historical  Sketch  of  Oil  and  Gas  Development  in  Alabama. 
Oil  Trade  Jnl  (Apr.,  1918)  9,  133. 


DOUGLAS    R.    SEMMES 


141 


to  300  ft.)  and  thorough  dissection,  well  wooded,  and  of  little  agricultural 
importance;  and  (3)  the  Tennessee  Valley  region  of  horizontal  or  gently 
warped  Pennsylvanian  and  Mississippian  strata,  where  the  relief  is  not 
so  marked,  the  wooded  area  is  less  extensive,  and  the  country  is  of  more 
importance  agriculturally. 


60  65 


Cretaceous 


Carboniferous 


Isouolue  Determined' 


Devonian-Cambrian 
Isouolue  Inferred 


H  Igneous  and 
II  Metamorphic 

GEOLOGICAL  MAP  OF  NORTHERN  ALABAMA,  SHOWING  CARBON  RATIOS. 


STRATIGRAPHY 

The  following  generalized  section  gives  an  approximate  idea  of  the 
thickness  and  lithologic  character  of  the  formations  of  the  region  as  a 
whole.  The  Carboniferous  series,  especially,  shows  lateral  variations 
of  striking  prominence,  but  certain  horizons  are  persistent  throughout 
the  area. 

Of  these  formations  the  Carboniferous  cover  much  the  larger 
part  of  the  whole  region,  the  Pennsylvanian,  or  Coal  Measures, 
forming  the  surface  throughout  large  portions  of  Cullman,  Winston, 
Walker,  Blount,  Jefferson,  and  Tuscaloosa  Counties,  and  the  Mississip- 


142 


OIL   POSSIBILITIES   IN   NORTHERN   ALABAMA 


STRATIGRAPHIC  SECTION  FOR  NORTHERN  ALABAMA 


AGE 

Pleistocene 
Pliocene 


Cretaceous 


FORMATION 
NAME 

Lafayette 


Tuscaloosa 


Pennsylvanian    Coal 

measures 


Upper  Missis-     Mountain 
sippian  limestone 


Lower  Missis-     Fort  Payne 
sippian  chert 


THICKNESS  LITHOLOQIC  CHARACTER 

AND  SUBDIVISIONS 

0-  50  Unconsolidated  and  semiconsoli- 
dated  gravels  and  sands.  Red, 
pinkish,  maroon,  and  whitish 
clays. 

0-1000  Gravels,  sands,  and  clays.  Red  to 
gray  or  white.  Non-marine. 

200-2500  Shales,  arenaceous  shales,  massive 
sandstones,  and  conglomerates 
near  base.  Basal  conglomer- 
ate, or  Millstone  grit.  Coal 
seams. 

400-  900  Massive  bluish  crinoidal  lime- 
stone (Bangor  limestone),  over- 
lying a  series  of  coarse  to 
medium-grained  sandstones  with 
alternating  thinner  beds  of  lime- 
stones and  shales.  Thick,  lo- 
cally massive,  brown  sandstones 
at  base  (Hartselle  sandstone). 

200-  500  Cherty  limestone  or  limestones 
with  thin  chert  seams  or  layers 
of  nodules.  Readily  eroded, 
valley-making  formation  (Tus- 
cumbia  limestone).  This  over- 
lies a  series  of  hard  cherts 
(Lauderdale  chert),  very  re- 
sistant to  erosion  and  forming 
prominent  ridges. 

0-  50  Black,  highly  bituminous  shales 
and  locally  thin  sandstones  and 
bluish  shales. 

200-  400        Shales,  limestones  (Niagara),  and 
ferruginous  sandstones  and  some 
conglomerates.     Iron  ores. 
Bluish,  thin-bedded  limestone  (Pel- 
ham     or    Chickamauga)     with 
coarse-grained  siliceous  layers, 
Unconformity  making  excellent  oil  sands. 

Sharply  folded  and  faulted  thick- 
2000-3300  bedded  crystalline  dolomite  with 

chert  seams,  overlying  600  ft.  of 
thick-bedded  non-cherty  gray 
crystalline  dolomite. 

1000-1500        Thin-bedded   blue  limestone  and 
gray  and  yellow  shales. 

pian  forming  the  surface  in  Madison,  Limestone,  Lawrence,  Lauderdale, 
and  Colbert  Counties.  To  the  west,  the  Carboniferous  strata  are  over- 
lapped by  the  Cretaceous,  which  in  turn  is  covered  in  places  by  the 
Lafayette,  but  throughout  a  large  part  of  this  Cretaceous  area  the  under- 


Devonian  Black  shale 


Silurian 
Ordovician 


Clinton 


Unconformity  (?) 
Trenton 
limestone  500-1000 


Knox 
dolomite 


Cambrian  Coosa  shales 


DOUGLAS   R.    SEMMES  143 

lying  Coal  Measures  are  exposed  along  the  courses  of  the  principal 
streams.  The  pre-Carboniferous  rocks  are  only  exposed  in  small 
areas  in  the  north,  along  the  anticlinal  valleys  farther  south,  and  in  the 
Coosa  Valley. 

Oil  and  Gas  Horizons 

The  possible  oil  and  gas  horizons  throughout  the  section  are  rather 
numerous;  many  of  these  horizons  have,  locally,  given  very  promising 
shows.  Owing  to  the  striking  lateral  variations  in  lithologic  character, 
horizons  that  may  at  one  point  be  promising  have  little  or  no  possibilities 
at  another;  this  is  especially  true  in  the  Carboniferous  series. 

Pennsylvanian  Horizons 

In  the  Fayette  gas  field  in  Fayette  County,  the  wells  encountered 
the  first  shows  at  about  500  ft.  (152  m.)  below  sea  level,  or  at  a  depth  of 
from  850  to  950  ft.  (259  to  289  m.).  This  sandstone,  though  giving  good 
shows  of  oil,  proved  of  no  value  and  the  wells  were  continued  500  ft. 
lower  and  there  encountered  the  Fayette  gas  sand  proper,  a  soft,  white 
sand  of  excellent  quality.  The  best  well  of  this  group  was  estimated  at 
4,000,000  cu.  ft.  (112,000  cu.  m.)  per  day.  At  other  points,  the  sand  was 
found  more  tightly  cemented  and  proved  less  productive.  About  200 
ft.  below  the  Fayette  sand  a  thick  sandstone  (250  ft.)  was  encountered, 
which  also  gave  gas  shows  and  is  locally  known  as  the  Second  Gas  sand. 
Drilling  has  been  continued  900  ft.  below  the  Fayette  sand  and  another 
thick  sandstone,  containing  salt  water,  was  encountered  near  the  bottom. 
This  sandstone  has  been  correlated  with  the  Pine  sandstone  member  of 
the  Birmingham  Folio,  in  which  case  the  Fayette  sand  should  be  under- 
lain by  some  1000  ft.  of  shales  and  massive  sandstones  to  the  base  of 
the  Pine  sandstone,  then  500  ft.  of  shales  and  shaly  sandstones,  and  finally 
500  ft.  more  or  less  of  massive  sandstones  with  conglomerates  at  the  base 
(Millstone  grit).  In  other  words,  the  Fayette  gas  sand  should  be  about 
2000  ft.  above  the  base  of  the  Pennsylvanian,  if  maximum  thicknesses 
were  represented.  Deep  borings  in  the  area  have  shown,  however, 
that  the  total  thickness  of  the  Pennsylvanian  is  not  over  2500  ft.,  or 
only  about  1200  ft.  of  sediments  underlie  the  Fayette  sand.  It  should 
be  remembered,  moreover,  that  in  the  Birmingham  district  the  Boyles 
sandstone  (Pine  sandstone)  is  found  lying  directly  on  the  Bangor  lime- 
stones of  Mississippian  age,  representing  a  hiatus  of  much  over  2000  ft. 
of  sediments.  The  two  basal  sandstones  of  the  Coal  Measures,  the  Pine 
sandstone  and  the  Millstone  grit,  can  be  considered  as  possible  oil  hori- 
zons, but  owing  to  their  great  thickness,  thorough  cementation,  and 
massive  character,  as  well  as  the  fact  that  they  have  no  adequate  source 
of  oil  below,  the  writer  would  not  consider  them  horizons  worthy  in  them- 
selves of  extensive  testing. 


144  OIL  POSSIBILITIES   IN   NORTHERN  ALABAMA 

Mississippian  Horizons 

As  early  as  1865,  wells  were  drilled  in  Lawrence  County  in  the  vicinity 
of  asphaltum  and  maltha  showings  in  Mississippian  strata,  and  the  major- 
ity of  all  such  occurrences  of  bitumen,  maltha,  and  asphaltum  that  have 
been  reported  since  are  in  these  formations.  In  the  Bangor  limestone, 
many  such  occurrences  have  been  found  and  it  is  not  unreasonable  to 
suppose  that  a  sandy  layer  in  this  limestone  might  prove  a  paying  oil 
sand.  Below  the  Bangor  comes  the  Hartselle  group  of  thick  sandstones 
and  interbedded  limestones.  In  Morgan,  Lawrence,  and  Franklin 
Counties,  numerous  seeps  have  been  found  in  the  Hartselle,  and,  in 
many  places,  this  group  is  found  saturated  with  residual  petroleum. 
In  many  localities  this  sandstone  is  coarse-grained  and  friable,  with  a 
large  amount  of  pore  space,  which  should  make  it  an  excellent  oil  sand; 
but  elsewhere  it  is  fine-grained  and  highly  cemented  and  has  so  little 
pore  space  that  it  is  improbable  that  it  would  prove  a  pay  sand.  Un- 
fortunately, no  good  test  has  been  made  in  this  horizon  as  none  of  the 
wells  started  in  the  Pennsylvanian  has  reached  this  depth,  while  those 
started  below  the  Pennsylvanian  have  usually  commenced  operations 
on  the  Hartselle  itself,  or  immediately  above  it.  The  Lower  Mississip- 
pian Tuscumbia  limestone  has  given  rather  promising  shows  in  certain 
recent  tests.  In  it  are  found  sandy  horizons  that,  according  to  the  driller's 
statement,  make  excellent  oil  sands. 

Trenton  Horizons 

The  only  well  that  has  struck  oil  in  commercial  quantities  in  Alabama 
found  it  in  the  Trenton  (Pelham)  limestone.  This  horizon  is,  in  the 
opinion  of  the  writer,  the  most  favorable  for  commercial  oil  and  gas  to 
be  found  in  the  northern  part  of  the  state.  The  Trenton  series  is  com- 
posed of  thin-bedded  bluish  and  shaly  limestones,  throughout  which 
there  are  horizons  of  coarse-grained,  sandy  limestones  making  good  oil 
sands.  The  well  mentioned  (Goyer  No.  1),  drilled  in  1891,  is  located  in 
the  southwest  quarter  of  the  southeast  quarter  of  sec.  29,  T.  7N,  R  6W, 
Lawrence  County,  and  was  not  a  geological  location.  A  log  of  this  well3 
is  as  follows: 

FEET 

36  Soil 10 

35  Limestones;  Bangor 290 

34  Sandstones;  first  gas,  in  the  upper  part 35 

33  Shales;  a  dark  blue  color 110 

32  Limestone;  of  a  pearly  white,  sulfuretted  hydrogen  gas  was  struck  in  this 
rock  at  55  ft.  below  its  top  and  salt  water  at  53  ft.  from  its  top;  the  salt 

water  on  evaporation  gave  a  good  flavored  salt 80 

31  Limestone;  of  a  light  drab  color 320 

*  McCalley's  Tennessee  Valley  Report,  239. 


DOUGLAS   R.   SEMMES  145 

FEET 
30  Limestone;  impure,  coming  out  as  a  coarse  powder  like  corn  meal  and  hence 

called  "corn-meal  sand" 28 

29  Shales;  Devonian,  black 32 

28  Limestones;  shaly 17 

27  Limestones;  blue 2 

26  Shales;  sandy  and  of  a  mottled  (red  and  white)  color 9 

25  Limestone;  it  carries  some  little  oil 422 

24  A  gritty  calcareous  sand,  likely  from  'an  impure  limestone 100 

23  Limestone;  blue 45 

22  Limestone;  coarse  grained,  the  lower  5  ft.  is  an  oil  sand  though  it  carries 

no  oil 9 

21  Limestone;  coarse  grained,  impure  and  siliceous,  a  good  oil  sand 20 

20  Limestone;  blue 261 

19  Limestone;  white 32 

18  Limestone;  blue  with  greenish  specks 6 

17  Limestone;  white  or  cream  colored 6 

16  Limestone;  blue 63 

15  Limestone;  bluish  with  a  slight  reddish  tinge 26 

14  Limestone;  white 27 

13  Limestone;  gray  with  a  slight  reddish  tinge 4 

12  Limestone;  white 4 

11  Limestone;  gray  with  a  few  reddish  specks 3 

10  Limestone;  of  a  light  gray  color 49 

9  Limestone;  white 5 

8  Limestone;  of  light  gray  and  reddish  specks 2 

7  Limestone;  of  a  brownish  gray  color 5 

6  Limestone;  white * 4 

5  Limestone;  of  a  grayish  color  with  white  and  blue  specks 7 

4  Limestone;  with  large  white  specks  that  resemble  pieces  of  fossils 4 

3  A  dark  grayish  powder  with  blue  and  white  specks;  it  may  be  shale 5 

2  Limestone;  with  white  and  light  gray  colors  with  reddish  specks 22 

1  Limestone;  white 3 

Of  this  above  log,  35  is  in  the  Bangor  limestone,  from  34  down  into 
32  is  the  Hartselle  sandstone  group;  from  32  to  30  is  the  Tuscumbia 
limestone  and  Lauderdale  chert;  29  is  the  Devonian;  and  the  rest  is 
Trenton. 

The  pay  sand  in  this  well  was  found  625  ft.  (190  m.)  below  the  De- 
vonian. The  well  was  estimated  at  25  bbl.,  but  owing  to  the  collapse 
of  the  casing  and  the  letting  in  of  salt  water  the  well  was  lost.  The  oil 
was  of  a  light  greenish  color  and  had  a  specific  gravity  of  38.7°  Be. 

Knox  Horizon 

The  Cambro-Ordovician  Knox  dolomite  has  occasionally  given  small 
shows  of  gas;  and  since  dolomitization  with  its  attendant  shrinkage 
should  indicate  increase  in  pore  space  and  in  capacity  as  a  reservoir, 
this  formation  has  been  tested  several  times  in  the  hope  of  its  proving 
productive.  But,  as  the  Knox  lies  unconformably  below  the  Trenton 
and  where  exposed  shows  a  high  degree  of  deformation,  its  possibilities 
are  so  slight  as  to  be  unworthy  of  serious  consideration. 

VOL.   LXV. 10. 


146  OIL   POSSIBILITIES   IN   NORTHERN   ALABAMA 

STRUCTURAL  FEATURES 

The  Coosa  Valley  region  and  the  adjacent  outlying  valleys  are  char- 
acterized by  a  rather  intense  type  of  parallel  folds,  trending  northeast 
and  southwest,  with  which  are  occasionally  associated  faults  showing 
displacements  as  great  as  3000  ft.  (914  m.).  In  many  of  these  folds,  the 
Ordovician  formations  are  exposed  and,  consequently,  have  no  pos- 
sibilities as  oil  traps.  In  addition  to  the  northeastern  series  of  prominent 
Appalachian-type  folds,  there  is  a  series  of  undulations  running  northwest 
and  southeast.  These  folds,  or  "waves"  as  they  have  been  termed  by 
the  earlier  writers,  are  sometimes  quite  pronounced  and  show  a  reversal 
of  100  ft.  or  more.  At  the  intersection  of  these  undulations  quaquaversal 
structures  are  formed,  such  as  the  Blount  Springs  dome,  which  should 
make  excellent  oil  traps  if  the  oil  horizons  themselves  are  not  exposed. 
The  intensity  of  the  deformation  of  this  area,  however,  is  considered  an 
unfavorable  factor  in  the  development  of  valuable  accumulations  of  oil. 

In  the  Plateau  region,  running  parallel  to  the  Appalachian  folds 
farther  east  and  south,  there  is  a  series  of  subsidiary  undulations,  which 
can  be  traced  out  in  the  beds  of  the  Coal  Measures.  In  this  area  are 
likewise  developed  the  series  of  northwest-southeast  waves,  and  at  the 
intersection  of  these  two  series  more  or  less  perfectly  developed  domes 
are  occasionally  established.  Unfortunately,  the  most  favorable  portion 
of  the  Pennsylvanian  area,  the  western  part,  is  rather  extensively  covered 
by  the  Lafayette  gravels  and  the  Cretaceous  series,  or  by  a  mantle  of 
residual  soil,  which  makes  the  locating  of  favorable  structures  a  difficult 
task;  and  after  evidence  of  folding  has  been  found,  it  is  often  impossible 
to  map  the  structures  in  detail. 

In  the  Tennessee  Valley  region,  especially  in  the  area  underlain  by 
the  Mountain  Limestone  group  (Morgan,  Lawrence,  Franklin,  and  Col- 
bert Counties),  the  two  series  of  undulations  can  be  readily  detected; 
and  owing  to  the  character  of  the  surface  rock  the  structure  can  be 
accurately  mapped.  Since  the  most  favorable  oil  horizon,  the  Trenton, 
occurs  in  this  area  at  a  depth  of  1000  to  2000  ft.,  the  area  is  considered 
very  favorable  for  future  prospecting. 

SIGNIFICANCE  OF  CARBON  RATIOS  OF  COALS  OF  AREA 

A  recent  paper  by  Fuller,4  discussing  the  relation  of  the  carbon  ratios 
of  the  Pennsylvanian  coals  to  the  oil  fields  of  northern  Texas,  has  interested 
the  writer  in  collecting  and  plotting  the  fixed  carbon  percentages  of  the 
Pennsylvanian  coals  of  northern  Alabama.6  In  certain  localities,  a 

4  Myron  L.  Fuller :  Relation  of  Oil  to  Carbon  Ratios  of  Pennsylvanian  Coals  in 
North  Texas.  Econ.  Geol.  (1919)  14,  536. 

6  For  these  analyses  the  writer  is  indebted  to  the  publications  of  the  U.  S.  Bureau 
of  Mines,  to  the  Geological  Survey  of  Alabama,  and  to  R.  S.  Hodges,  chemist  of 
the  Geological  Survey. 


DOUGLAS   E.    SEMMES  147 

sufficient  number  of  analyses  were  obtainable  to  locate  the  isocarbs6 
definitely;  in  other  areas,  their  location  was  largely  inferred.  On  the 
accompanying  map,  the  direct  relationship  between  the  fixed  carbon 
and  the  amount  of  deformation  is  very  apparent.  Even  such  outlying 
folds  as  the  Sequatchie  anticline  have  their  definite  effect  upon  the 
percentage  of  fixed  carbon  in  the  coals  mined  along  their  flanks.  The 
degree  of  metamorphism  attending  this  deformation  has  been  shown  by 
David  White7  to  be  definitely  related  to  the  distribution  and  composition 
of  the  oils  found  in  the  formations  affected.  When  metamorphism  has 
reached  such  an  extent  that  the  fixed  carbon  in  the  coals,  considered  on  a 
basis  of  pure  coal,  has  reached  a  percentage  of  70,  it  is  very  improbable 
that  oil  pools  of  commercial  importance  will  be  found.  In  the  case  of 
northern  Alabama,  the  writer  believes  that  all  areas  where  the  fixed 
carbon  runs  as  high  as  65  per  cent,  may  be  considered  as  unfavorable 
territory  and  unworthy  of  extensive  tests,  until  at  least  the  areas  of  lower 
percentages  have  been  tested  and  oil  found  in  paying  quantities.  An 
examination  of  the  accompanying  map  shows  that  the  65-per  cent, 
isocarb  becomes  definitely  fixed  near  Huntsville  and  swings  southward 
and  westward  across  Madison,  Marshall,  Cullman,  and  Blount  Counties, 
and  along  the  northwestern  line  of  Jefferson  County,  thence  across 
Tuscaloosa  County,  swinging  around  the  southwestern  end  of  Jones' 
Valley  anticline  into  Shelby  County,  thence  southward  again  following 
the  crystalline  area.  Farther  east,  the  70-per  cent,  and  the  75-per  cent, 
isocarbs  swing  around  the  areas  of  more  intense  folding  and  attendant 
metamorphism.  To  the  north  and  west  of  the  65-per  cent,  isocarb, 
the  60-per  cent,  isocarb  is  less  definitely  located;  and  owing  to  the  scarcity 
of  analyses  of  the  coals  of  Marion  and  Franklin  Counties,  the  location 
of  the  55-per  cent,  isocarb  is  in  part  inferred. 

Favorable  Areas 

If  we  are  to  consider  the  relation  between  metamorphism  and  oil 
distribution  and  composition  as  established,  we  are  led  to  the  conclusion 
that  all  the  Coosa  Valley  region  and  much  of  the  Plateau  Region  is 
unfavorable  territory,  and  would  expect  in  this  area  only  small  ac- 
cumulations of  light  oil.  West  and  north  of  the  65-per  cent,  isocarb 
there  should  be  better  chances  for  larger  accumulations,  provided  we  have 
the  other  necessary  requirements  of  favorable  section  and  structure. 

The  Pennsylvanian  series  shows  a  fairly  favorable  section,  several 
good  sands,  and  good  structure  where  it  can  be  worked  out.  Most  of  the 

6  The  term  "  isocarb  "  has  been  adopted  by  David  White,  to  signify  a  line  drawn 
through  points  of  equal  carbon  ratio. 

7  David  White:  Some  Relations  in  Origin  between  Coal  and  Petroleum.     Jnl. 
Wash.  Acad.  Sci.  (Mar.  16,  1915)  6,  189. 

David  White :  Late  Theories  Regarding  the  Origin  of  Oil.    Bull.  Geol.  Soc.  Amer. 
(1917)  28,  727. 


148  OIL   POSSIBILITIES   IN   NORTHERN   ALABAMA 

area  underlain  by  the  Coal  Measures  lies  within  the  65-per  cent,  isocarb; 
to  the  west,  the  Coal  Measures  are  covered  by  the  Lafayette  and 
Cretaceous  formations.  In  the  Fayette  district,  which  is  near  the  55- 
per  cent,  isocarb,  only  gas  was  found  in  paying  quantities,  which  would 
indicate  that  the  degree  of  metamorphism  was  still  too  great  for 
accumulation  of  oil.  Considering,  therefore,  all  evidence  obtained  so 
far,  the  Pennsylvanian  area  is  not  considered  favorable  territory  except 
toward  the  western  line  of  the  state.  In  this  area  a  hole  drilled  to  2500 
or  3000  ft.  would  test  the  Hartselle  sandstone  as  well  as  the  Pennsylvanian 
horizons. 

To  the  north,  the  Pennsylvanian  formations  break  off  forming  a  pro- 
nounced scarp  facing  the  north.  Passing  down  over  this  scarp,  one  comes 
upon  a  fairly  level  plain  underlain  by  the  lower  members  of  the  Bangor 
limestone.  The  upper,  more  massive  members  of  this  limestone  form 
the  base  of  the  scarp.  Farther  north,  beyond  the  plain  underlain 
by  the  lower  Bangor  limestone,  another  scarp  is  formed  by  the  Hartselle 
sandstone,  locally  known  as  Little  Mountain.  Between  these  two  scarps 
there  might  be  found  favorable  structure,  where  the  Hartselle  is  suf- 
ficiently covered  to  prove  productive;  this  area  is  rather  limited,  however, 
for  which  reason  practically  no  tests  have  been  made  of  the  Mississippian 
horizons. 

By  drilling  at  any  point  north  of  the  Pennsylvanian  scarp,  the  upper 
Trenton  horizons  (Goyer  horizon)  would  be  encountered  not  more  than 
2000  ft.  (609  m.)  in  depth.  This  would  give  a  large  territory  comprising 
most  of  Morgan,  Lawrence,  Colbert,  and  parts  of  Franklin  and  Lauder- 
dale  Counties,  in  which  the  type  of  structures  commonly  considered 
as  oil  traps  are  fairly  abundant,  the  degree  of  metamorphism  is  compara- 
tively low,  and  the  section  is  decidedly  favorable.  It  is  in  this  area,  and 
especially  in  Franklin,  Colbert,  and  Lawrence  Counties,  that  the  writer 
would  suggest  that  future  tests  be  made.  Numerous  anticlinal  folds 
can  be  found  in  the  Hartselle  sandstones  and  in  places  definite  closure 
can  be  worked  out. 

Past  and  Present  Development 

The  extent  and  results  of  past  development  in  northern  Alabama  have 
been  fully  described  by  Doctor  Smith  in  his  historical  sketch  of  develop- 
ments already  cited.  The  more  important  of  these  tests,  with  their 
dates  and  producing  horizons,  are  as  follows: 

1865.  Watson  wells,  southeastern  Lawrence  County;  good  shows  in  two  wells; 
Trenton  horizon. 

1890.  Newmarket  well,  Madison  County;  strong  petroleum  odor,  but  no  sand; 
Trenton  horizon. 

1891.  Goyer  wells,  southeastern  Lawrence  County;  one  estimated  at  25  bbl. 
a  day;  Trenton  horizon. 


DOUGLAS   R.    SEMMES  149 

1893.  Allen  wells,  Florence,  Lauderdale  County;  one  dry,  the  other  showed 
small  quantities  of  very  light  oil  and  some  gas,  well  spoiled  by  shooting;  Trenton 
horizon. 

1904-5.  Huntsville  and  Hazel  Green,  Madison  County;  gas  shows  at  both 
localities;  Trenton  horizon. 

1909.  Fayette  wells,  Fayette  County;  one  estimated  at  4,000,000  cu.  ft.  of  gas; 
Pennsylvanian  horizon. 

1910-11.  Shannon  wells,  Jasper,  Walker  County;  50,000  cu.  ft.  of  gas,  oil  show; 
Pennsylvanian  horizon. 

1911-12.  Woodward  Iron  Co.,  Russellville,  Franklin  County;  small  gas  show 
in  Knox  dolomite  (?). 

1912.     Bryan,  Jefferson  County;  oil  and  gas  show;  Pennsylvanian  horizon. 

1916.  Cordova,  Walker  County;  good  show,  black  residual  oil;  Pennsylvanian 
horizon. 

1917-18.  Atwood  well,  Franklin  County;  gas  indications;  Pennsylvanian 
horizon. 

1917-18.  Aldrich  Dome  wells,  6  mi.  southeast  of  Birmingham,  Jefferson  County; 
gas  shows;  Pennsylvanian  horizon. 

1918.  Guin  well,  Lamar  County;  oil  shows  in  two  sands;  Pennsylvanian  horizon. 

1919.  Hobson  well,  Frankford,  Franklin  County;  drilling  at  1765  ft.   (Dec.), 
small  oil  and  gas  shows;  Trenton  horizon. 

The  evidence  of  the  above  tests  strongly  supports  the  carbon  ratio 
hypothesis,  as  all  localities  near  the  65-per  cent,  isocarb  showed  gas 
and  only  small  shows  of  oil.  The  heavy  oil  found  at  Cordova  (26.5°  Be") 
is  an  exception,  but  this  was  undoubtedly  a  pocket  of  residual  oil,  the 
lighter  volatile  constituents  of  which  had  been  driven  off. 

Future  Prospecting 

The  area  the  writer  considers  most  favorable  for  future  testing  is  the 
northwestern  portion  of  the  state,  where  the  Trenton  limestone  would  be 
the  producing  horizon.  Even  this  area  is  not  without  its  disadvantages. 
The  degree  of  metamorphism  increases  not  only  near  areas  of  deformation 
but  in  depth  in  any  locality.  Therefore  the  degree  of  metamorphism 
of  the  Ordovician  formations,  once  covered  to  great  depth  by  the  Penn- 
sylvanian series,  may  be  much  greater  than  is  indicated  by  the  Penn- 
sylvanian coals,  in  which  case  commercial  accumulations  would  be 
improbable.  Moreover,  there  is  a  possibility  of  an  unconformity  below 
the  Silurian.  Nevertheless,  considering  the  structure,  the  lithologic 
character  of  the  section,  and  the  evidence  of  the  carbon  ratios  of  the 
overlying  Pennsylvanian  coals,  the  area  is  undoubtedly  worthy  of  further 
tests,  provided  they  be  well  located  on  carefully  determined  structure. 
In  addition  to  this  area,  the  Coal  Measures,  where  exposed  in  Winston, 
Marion,  and  Fayette  Counties,  should  be  well  worth  testing,  especially 
where  drilling  is  continued  to  sufficient  depths  to  test  the  Hartselle  and 
the  Trenton  horizons. 


150  OIL   POSSIBILITIES   IN   NORTHERN   ALABAMA 

DISCUSSION 

DAVID  WHITE,  Washington,  D.  C. — Pessimism  regarding  the  ca- 
pacity of  the  Hartselle  sandstone  of  Alabama  should  be  discouraged. 
The  outcropping  sandstone  south  of  Tuscombia  carries  asphalt  seepages 
that  are  still  fresh.  In  fact,  the  sandstone  was  once  drilled  near  this 
outcrop.  The  Hartselle  is  remarkably  persistent  throughout  a  great 
area,  and,  in  regions  where  the  carbonization  of  the  organic  debris 
has  not  progressed  too  far,  this  sandstone  offers  oil  possibilities  in  favor- 
able structures. 

It  is  possible  that  the  Carboniferous  of  western  Alabama,  beyond 
the  zone  of  too  great  carbonization,  may  contain  oil  deposits  as  important 
as  any  to  be  found  in  the  arches  of  the  Coastal  Plain  formations. 

MOWRY  BATES,  Tulsa,  Okla. — Last  spring  I  examined  diamond-drill 
cores  of  Hartselle  sandstone  from  holes  drilled  in  nearly  every  section 
of  Alabama.  Every  core  showed  oil  but  it  was  thick  and  the  sand 
was  so  tight  that  it  was  impossible  to  move  the  oil.  Under  the  microscope 
no  pore  spaces  could  be  found.  None  of  these  wells  have  shown  oil  in 
appreciable  amounts. 


RESUME    OF   PENNSYLVANIA-NEW   YORK   OIL   FIELD  151 


Resume  of  Pennsylvania-New  York  Oil  Field 

BY  ROSWELL  H.  JOHNSON,  M.  S.,  AND  STIRLING  HUNTLEY,  PITTSBURGH,  PA. 

(New  York  Meeting,  February,  1920) 

PENNSYLVANIA  will  be  remembered,  as  long  as  oil  is  produced,  as  the 
cradle  of  the  industry  of  petroleum  in  North  America.  It  was  on  Oil 
Creek,  near  Titusville,  Venango  Co.,  that  Col.  Edwin  L.  Drake,  superin- 
tendent for  the  Seneca  Oil  Co.,  brought  in  the  first  commercial  oil  well 
on  Aug.  28,  1859.  Great  difficulty  was  experienced  in  getting  the  well 
down  to  the  producing  depth  of  69  ft.  (21  m.)  with  the  spring-pole 
system  then  in  vogue  for  punching  shallow  water  wells,  so  the  novel 
expedient  of  driving  an  iron  tube  through  the  surface  clays  and  quicksand 
was  finally  resorted  to.  The  well  had  an  initial  yield  of  25  bbl.  a  day 
on  the  pump,  but  soon  went  off,  though  2000  bbl.  were  produced  by 
the  end  of  the  year. 

With  the  Drake  well  a  success,  a  young  industry  sprang  into  being, 
the  rapid  growth  of  which  has  been  second  to  none  in  the  country  and 
the  value  of  whose  product  is  only  surpassed  by  that  of  coal.  For 
years  the  only  producing  territory,  the  Pennsylvania-New  York  field 
attained  its  greatest  production  in  1891,  when  the  bringing  in  of  the  Mc- 
Donald pool,  between  Pittsburgh  and  the  West  Virginia  line,  gave  a  total 
of  over  33,000,000  bbl.  At  present  the  field,  combined  with  West  Vir- 
ginia and  southeast  Ohio,  gives  25,000,000  barrels. 

GEOLOGY  AND  STRATIGRAPHY 

In  general,  the  Appalachian  field  is  a  huge  geosyncline,  the  axis  of 
which  runs  roughly  northeast-southwest,  from  north  of  the  New  York 
state  line  south  through  Brookeville,  Kittanning,  Pittsburgh,  Wash- 
ington, through  the  southwest  corner  of  the  state  of  Pennsylvania  into 
West  Virginia.  Minor  folding  has  accompanied  or  followed  the 
dominant  fold  of  the  field,  and  it  is  from  these  structures  near  the 
Pennsylvania- West  Virginia  line  and  their  influence  on  the  accumulation 
of  oil  and  gas  that  I.  C.  White,  state  geologist  of  West  Virginia,  obtained 
his  evidence  for  anticlinal  guidance  of  prospecting. 

Many  horizons  in  the  geologic  column  of  the  field  serve  as  reservoirs, 
and  there  are  several  pools  that  have  wells  producing  side  by  side  from 
different  and  widely  vertically  separated  strata.  The  strata  show  a 
promising  succession  of  porous  sand  and  conglomerate  horizons  alter- 
nating with  numerous  gray  and  dark  brown  or  black  shales,  admittedly 


152  R£STJM£  OF  PENNSYLVANIA-NEW  YORK  OIL  FIELD 

the  ideal  section.  In  southwestern  Pennsylvania  and  northern  West 
Virginia,  for  the  last  few  years,  deep  wells  have  been  drilled  in  the  hope 
of  revealing  new  deep  gas  reservoirs.  It  is  interesting  to  note  that  the 
last  two  wells  have  established  deep  drilling  records  for  the  world,  the 
last,  the  Hope  Natural  Gas  Co.,  on  the  Lake  farm,  12  mi.  east  of  Fair- 
mont, W.  Va.,  having  reached  a  depth  of  7579  ft.  (2311  m.) 

As  a  rule,  in  the  Pennsylvania-New  York  field,  the  dips  in  the  pro- 
ducing oil  fields  are  very  gentle  with  the  exception  of  the  Gaines  pool, 
producing  from  a  fissured  shale  horizon,  which  has  dips  ranging  up  to 
30°.  The  sand  bodies,  though  locally  lenticular,  are  on  the  whole 
fairly  persistent.  Indeed,  with  so  many  sand  horizons,  an  operator 
usually  considers  that  he  has  a  good  chance  in  deeper  drilling,  even 
though  his  principal  sand  is  poor  or  absent. 

Pennsylvania  production  runs  from  the  top  of  the  Conemaugh  to 
the  base  of  the  Chemung.  The  Murphy,  Cow  Run,  and  Dunkard  sands 
are  in  the  Conemaugh;  the  Maxon  appears  in  the  Mauch  Chunk  shale; 
and  in  the  Pocono  sandstone,  below  the  Greenbrier  limestone,  are  found 
the  Big  Injun,  Squaw,  Papoose,  Butler,  Berea,  Gantz,  Fifty-foot,  and 
Hundred-foot  sands.  In  the  Catskill  occur  the  Ninevah,  Snee,  Gordon, 
Fourth,  Fifth,  and  Sixth  sands;  and  in  the  upper  Chemung  are  the 
Elizabeth,  Warren,  Speechley,  Tiona,  Bradford,  Elk,  and  Kane  sands. 

In  the  latter  part  of  1919,  a  gas  pool  was  developed  south  of  Mc- 
Keesport,  Pa.  where  the  dominant  structure  is  the  Murraysville  anti- 
cline, with  a  northeast-southwest  axis.  The  Foster-Brendel  No.  1  had 
an  extraordinarily  high  initial  flow  and  unusually  favorable  marketing 
conditions  enabled  it  to  yield  over  50,000,000  cu.  ft.  the  first  day  it  was 
controlled,  which  was  about  a  week  after  its  completion.  The  produc- 
tion is  from  the  Speechley  sand  at  a  little  below  3000  ft.  Lithology 
here  seems  to  play  a  more  important  part  than  structure.  Dry  holes 
drilled  along  the  axis  of  the  structure  revealed  a  dry  tightly  cemented 
sand,  which  until  recently  condemned  the  territory. 

The  lateral  limits  of  large  production  seem  to  be  fairly  well  estab- 
lished; and,  due  to  the  small  area  and  the  close  spacing  of  the  wells,  it 
is  expected  that  the  pool  will  have  a  short  life.  The  rock  pressure  has 
already  been  lowered  from  an  estimated  pressure  of  1450  Ib.  to  350  Ib. 
and  is  declining  at  about  3^  Ib.  a  day. 

The  excitement  over  the  one  really  large  well  has  led  to  unjustifiable 
claims  that  this  is  the  world's  largest  gas  field;  it  has  also  Jed  to  an 
orgy  of  promotion  and  speculation.  Except  the  Foster-Brendel  lease, 
the  pool  will  show  a  net  loss  to  the  producers. 

GRADE  OF  OIL 

Nearly  all  the  oil  of  the  field  is  listed  as  the  Pennsylvania  grade  and  is 
taken  the  world  over  as  a  criterion  of  high-grade  crude  oil.  It  is  a  light, 


ROSWELL   H.    JOHNSON   AND   STIRLING   HUNTLEY 


153 


greenish-colored  oil  with  paraffine  but  no  asphaltum.  It  varies  around 
44°  Be*,  and  has  a  high  gasoline  content.  It  has  always  commanded  a 
premium  over  other  grades,  and  its  present  price  of  $5.50  will  keep  alive 
many  old  wells  longer  than  seemed  probable  a  few  years  ago,  and  also 
noticeably  encourage  new  production.  Little  difficulty  is  experienced 
in  marketing  the  oil  and  gas  produced.  A  number  of  pipe  lines  collect 
the  runs  of  the  field  and  carry  them  either  to  one  of  the  several  refineries 
along  the  Allegheny  and  Ohio  Rivers,  or  to  one  of  the  large  pipe  lines, 
such  as  the  Tidewater  and  the  National  Transit,  which  run  down  to 
the  huge  refineries  of  the  Atlantic  seaboard. 

TABLE  1. — Natural  Gas  Production  of  Pennsylvania  in  1916-1917 


Year 

Volume  in 
1000  Cu.  Ft. 

Average  Price  in 
Cents  per  1000 
Cu.  Ft. 

Value 

1916        

130  483,705 

18  78 

$24  513  119 

1917  

133,397,206 

21.53 

28  716  492 

TABLE  2. — Natural  Gas-gasoline  Production  of  Pennsylvania  in  1916-1917 


Year 

Number 
of 
Operators 

Plants 

Gasoline  Produced 

Estimated 
Volume 
of  Gas 
Treated, 
1000  Cu.  Ft. 

Average 
Yield  of 
Gasoline 
per  1000 
Cu.  Ft. 

Number 

Daily 
Capacity, 
Gallons 

Quantity 
Gallons 

Value 

Price  per 
Gallon 
Cents 

1916 
1917 

167 
287 

195 
251 

46,487 
59,164 

9,714,926 
13,826,250 

$1,726,173 
2,778,098 

17.77 
20.01 

38,490,621 
49,487,056 

0.252 
0.279 

Great  numbers  of  gas-gasoline  plants  have  sprung  up  and  are  realizing 
handsome  returns  from  the  utilization  of  casing-head  gas  as  a  source 
of  gasoline,  before  turning^over  the  dry  gas  to  be  used  as  a  fuel.  The 
residual  gas  is  taken  up  by  public-utility  corporations  and  marketed  in 
the  nearby  industrial  centers  both  for  manufacturing  and  domestic  pur- 
poses. Pennsylvania  gas  seldom  has  nitrogen  in  important  amounts  and 
so  gives  an  average  heating  value  of  about  1000  B.t.u. 

The  increasing  scarcity  of  gas  in  this  field  has  been  a  source  of  con- 
siderable worry  both  to  householders  and  to  industries  dependent  on  it 
as  a  fuel.  The  scarcity  has  resulted^'n  the  gradual  increase  in  price  to 
consumers  and  a  careful  redevelopment  of  old  pools  and  a  utilization  of 
former  leakages  and  wastes.  The  recent  deep  drilling  was  the  direct  out- 
come of  this  search  for  deeper  'gas  to  replace  the  gas  from  present 
reservoirs,  which  are,  of  course,  gradually  becoming  exhausted. 

COSTS  AND  DRILLING 

The  cable-tool  system  was  developed  in  this  field  to  present  standards 
of  efficiency.  The  ranks  of  drillers  in  Kansas  and  Oklahoma  are  com- 


154  R^SUM       OF   PENNSYLVANIA-NEW   YORK    OIL   FIELD 

posed,  to  a  great  extent,  of  men  whose  apprenticeship  was  served  in  this 
field.  The  cost  of  drilling  has  risen  rapidly  in  this  field,  as  in  all  others, 
though  perhaps  not  in  so  great  a  measure  because  of  the  proximity  to  the 
iron  and  steel  supply  centers,  and  the  comparatively  greater  supply  of 
labor  at  hand.  The  Drake  well  was  69  ft.  deep ;  the  well  that  has  recently 
established  a  new  world's  record  is  7579  ft.  About  2000  ft.  may  be 
taken  as  a  fair  average  for  the  depth  of  present  drilling.  The  average 
cost  of  a  producing  well  is  about  $16,000,  although  the  variation  is  great. 
The  percentage  of  dry  holes  in  1918  has  been  estimated  to  be  22  per  cent. 

FUTURE  POSSIBILITIES 

In  view  of  the  long  period  of  testing  nearly  all  parts  of  the  field  since 
its  inception,  there  is  little  possibility  of  many  new  pools  of  considerable 
extent  or  production  being  brought  in  from  present  producing  horizons. 
Max  W.  Ball  estimates  the  present  per  cent,  of  exhaustion  of  the  field  at 
69.5  per  cent.  One  encouraging  feature  of  the  field,  however,  is  the  re- 
markable evidence  given  by  the  decline  curve  of  the  Appalachian  field. 
The  longevity  is  good,  which  is  to  be  attributed  mainly  to  the  high  price 
which  keeps  the  well  alive  for  a  long  period  after  the  rate  of  decline  has 
naturally  become  slow.  Here,  as  elsewhere,  close  drilling  gives  the  usual 
sharp  decline. 

It  is  a  remarkable  fact  that  the  land  near  the  Drake  discovery  well 
near  Titusville,  which  was  drilled  in  soon  after  the  date  of  that  well,  is 
still  producing.  The  great  richness  of  the  casing-head  gas  permits  some 
leases  in  this  field  to  be  operated  when  it  no  longer  pays  to  pump  the  wells. 
We  should  get  a  much  higher  extraction.  There  is  still  the  possibility 
of  the  deep  reservoirs  of  oil  and  gas,  which  was  the  goal  of  the  recent 
deep  drilling.  The  disappointing  results  to  date  should  not  be  taken  too 
seriously,  in  view  of  the  fact  that  these  wells  were  for  the  most  part  not 
on  the  strongly  marked  domes,  which  should  be  chosen  for  such  tests. 

DISCUSSION 

G.  H.  ASHLEY,  Harrisburg,  Pa. — There  are  two  or  three  things  re- 
garding Pennsylvania  that  are  of  interest.  Mr.  Johnson  spoke  of  the 
Gaines  oil  field  which  lies  far  east  of  the  main  oil  belt.  Another  oil  field, 
very  small,  occurs  near  Latrobe,  well  east  of  the  main  belt,  and  over  in 
Somerset  County  there  is  a  well  that  is  reported  to  have  yielded  some  oil. 
These  suggest  the  possibility  of  oil  over  all  of  the  gas,  or  eastern,  side  of 
the  field.  Again,  in  the  southeast  corner  of  this  state,  during  the  last 
year  or  two,  some  oil  has  been  found  in  seeps,  which  has  raised  the 
question  whether  there  may  not  be  commercial  oil  in  that  section.  The 
matter  is  one  we  are  still  studying.  We  are  not  quite  ready  to  say  that 


DISCUSSION  155 

the  oil  is  actually  coming  from  its  apparent  source,  that  is,  from  the  pre- 
Cambrian  rocks. 

Some  question  has  arisen  as  to  the  eastward  extent  of  the  gas  fields 
of  the  state.  On  the  flank  of  the  Chestnut  Ridge  anticline,  there  is  a 
little  bench  with  a  gas  pool,  and  a  little  gas  has  been  found  in  Cambria 
County  just  east  of  the  anticline.  These  facts  would  lead  to  the  suppo- 
sition that  there  might  be  gas  on  that  anticline,  but  all  efforts  so  far  have 
failed  to  show  any.1  The  only  explanation  we  can  give  for  the  failure 
to  find  gas  in  that  region  is  that  the  rock  there  is  not  favorable.  There  are 
other  places  in  the  state  where  the  structure  and  other  conditions  seem  to 
favor  the  presence  of  gas,  but  drilling  finds  none. 

1  Since  this  was  written,  a  drilling  of  the  Peoples  Gas  Co.,  in  the  center  of  the 
anticline  where  cut  by  Loyalhanna  Creek,  has  struck  300,000  ft.  of  gas  at  6822  ft. 


156  GEOLOGY   OP   CEMENT   OIL   FIELD 


Geology  of  Cement  Oil  Field 

BY  FREDERICK  G.  CLAPP,  NEW  YORK,  N.  Y. 

(New  York  Meeting,  February,  1920) 

ALTHOUGH  many  oil  fields  have  been,  and  still  are  being,  discovered 
in  Oklahoma,  the  geology  and  structure  of  most  of  them  have  not  become 
familiar  to  the  general  public  because  of  the  delay  in  securing  government 
geological  surveys  and  the  reluctance  of  oil  companies  and  other  inter- 
ested parties  to  give  out  their  "inside  information."  Therefore,  until 
official  surveys  are  available,  it  behooves  us  to  publish  geological  results 
as  soon  as  possible.  Fortunately  the  writer  has  been  authorized  by  the 
Cement  Field  Oil  Co.  to  publish  his  data  on  the  Cement  field,  Caddo 
County,  at  this  time. 

LOCALITY  AND  DESCRIPTION 

The  Cement  field  is  situated  in  the  part  of  Oklahoma  known  generally 
until  recently,  as  "Healdton  fields,"  and  lies  60  mi.  (96  km.)  northwest 
of  the  Healdton  field  proper.  Like  the  Healdton  field,  it  forms  an  ap- 
proximate ellipse,  trending  northwest  and  southeast  through  the  village 
of  Cement  on  the  St.  Louis-San  Francisco  Railroad,  on  which  it  is  reached 
in  2J£  hours  from  Oklahoma  City. 

In  its  geological  structure,  the  field  constitutes  an  anticline  over  13 
mi.  (21  km.)  long  and  from  1  to  3  mi.  wide;  the  point  of  greatest  width 
being  not  far  from  its  intersection  by  the  above-named  railroad.  The 
major  axis  trends  north  75°  west  from  the  village  of  Cement;  but  east- 
ward appears  deflected  (if  field  interpretations  are  correct)  to  about  south 
45°  east.  About  5  mi.  south  lies  an  approximately  parallel  syncline,  which 
may  be  conveniently  called  the  Cyril  syncline,  the  south  and  west  bounda- 
ries of  which  may  be  distant  many  miles,  but  forming  a  closed  basin 
south  of  the  Cement  anticline.  The  position  of  the  offsetting  synclinal 
axis,  which  is  believed  to  lie  north  and  east  of^Cement,  has  not  been 
discovered. 

TOPOGRAPHY 

In  the  southwest  part  of  the  state,  nearly  all  maps  of  Oklahoma  show 
two  mountain  areas — Arbuckle  and  Wichita — which  are  conspicuous 
geological  and  topographic  landmarks.  In  addition,  some  maps  show 
a  third,  and  smaller,  range,  named  the  Keechi  Hills,  in  the  vicinity  of 
Cement.  These  hills  also  form  a  conspicuous  feature  in  the  landscape; 
but  for  some  reason  they  have  been  neglected  by  geologists,  and  the 


FREDERICK   G.    CLAPP  157 

merest  references  to  them  have  appeared  in  state  and  private  reports. 
In  particular,  they  have  been  neglected  until  recently  by  oil  geologists. 
So  prominent  are  Keechi  Hills  that  they  can  be  seen  many  miles  away, 
rising  above  the  generally  rolling  agricultural  surface  in  the  form  of  mesa- 
like  and  conical  treeless  masses  100  to  400  ft.  (30  to  122  m.)  above  the 
neighboring  valleys.  Perhaps  their  dwarfing  by  Wichita  Mountains, 
visible  in  the  distance,  is  what  has  prevented  their  being  studied  and 
tested  for  oil  years  ago;  or,  perhaps  it  is  the  presence  of  the  sometimes 
pure  gypsum  rock  which  caps  the  isolated  mesas,  and  in  one  place  caps 
the  main  mass  of  Keechi  Hills.  The  relief  of  the  land  surface  in 
Keechi  Hills  is  about  500  ft.,  ranging  from  about  1150  ft.  above  sea- 
level  near  the  Little  Washita  River  on  the  east,  to  1630  ft.  on  the  crest 
of  Keechi  Hills. 

HISTORY  OF  DEVELOPMENTS  IN  CEMENT  FIELD 

The  first  development  took  place,  many  years  ago,  in  the  village  of 
Cement,  where  a  hole  was  sunk  only  a  few  hundred  feet  in  depth  and 
abandoned.  About  1916  a  well  was  started  on  the  Funk  farm  in  section 
6,  township  5  north,  range  8  west,  3  mi.  (4.8  km.)  east  of  Cement,  and  at 
1415  ft.  it  discovered  500,000  cu.  ft.  (14,000  cu.  m.)  of  gas  and  a  showing 
of  oil;  its  total  depth  is  1685  ft.  (513  m.)  Shallow  tests  were  also  drilled 
years  ago  in  township  6  north,  range  9  west,  3  mi.  northeast  of  Cement; 
and  in  section  21,  township  5  north,  range  8  west,  5  mi.  southeast  of  Ce- 
ment. The  first  real  excitement,  however,  was  caused,  about  1917,  by 
the  drilling  of  a  well  by  the  Oklahoma  Star  Oil  Co.,  on  the  Kunzmiller 
farm  in  the  southwest  quarter  of  section  32,  township  6  north,  range  9 
west,  2  mi.  northwest  of  Cement.  At  a  depth  of  about  1700  ft.,  an  un- 
known quantity  of  oil  was  found  which  flowed  into  the  tank.  The  pro- 
duction is  reported  to  have  been  10  to  25  bbl.  per  day;  but  we  have  no 
definite  information  on  the  subject,  except  that  it  still  flowed  slightly 
when  first  visited  by  the  writer  in  the  fall  of  1917.  The  main  point  of 
interest  is  that  the  oil  was  found  in  a  comparatively  shallow  sand  of 
Permian  age,  800  ft.  or  more  above  the  Fortuna,  or  next  important  group 
of  sands. 

In  September,  1917,  Fortuna  Oil  Co.  completed  a  gas  well  at  a  depth 
of  2340  ft.  and  an  initial  production  of  35,000,000  cu.  ft.  of  gas  per  day,  on 
the  Thomas  farm  in  the  southwest  corner  of  section  31,  township  6  north, 
range  9  west,  3  mi.  west  of  Cement  and  1%  mi.  west  of  the  Oklahoma 
Star  well.  In  1918,  the  first  weU  of  Prosperity  Oil  &  Gas  Co.,  in  the 
southeast  quarter  of  section  5,  township  5  north,  range  9  west,  was  drilled 
into  the  same  sand  at  a  depth  of  2345  ft.  and  obtained  a  flow  of  oil,  which 
has  been  variously  estimated  from  50  to  150  bbl.  per  day;  but  the  well 
was  badly  handled  and  was  thereafter  continued  in  an  effort  to  reach  the 
deeper  sands.  The  first  well  of  Gorton  Oil  &  Refining  Co.,  in  section  2, 


158  GEOLOGY   OF   CEMENT   OIL   FIELD 

township  5  north,  range  9  west  was  completed  in  1918,  having  an  esti- 
mated capacity  of  15,000,000  cu.  ft.  of  gas  per  day.  The  second  well  of 
the  Gorton  Oil  &  Refining  Co.,  known  as  the  " Betty  G,"  was  completed 
later  the  same  year  in  the  northwest  quarter  of  section  32,  township  6 
north,  range  9  west;  and  while  it  has  flowed  oiJ,  its  production  is  not  known, 
because  it  has  not  been  thoroughly  cleaned  out,  but  it  was  reported  to  be 
good  oil  well.  Fortuna  No.  2  well,  situated  in  the  northwest  quarter 
of  section  6,  township  5  north,  range  9  west  was  completed  in  December, 
1918,  with  an  initial  production  reported  at  150  bbl.  per  day.  The  oil 
is  from  the  same  sand  as  the  gas  in  Fortuna  No.  1,  1  mi.  to  the  north.  A 
few  days  later  the  first  well  of  Gladstone  Oil  &  Refining  Co.  in  southeast 
quarter  of  section  31,  township  6  north,  range  9  west  was  finished,  with 
a  reported  initial  production  of  90  bbl.  per  day.  Since  that  time  three 
other  oil  wells  have  been  drilled  along  the  north  flank  of  the  anticline,  and 
two  near  its  center.  Three  wells  are  now  being  drilled  or  about  to  be 
drilled  to  deeper  sand.  About  sixty  derricks  stand  in  the  field  at  the 
time  this  paper  is  printed. 

The  well  of  the  Cement  Field  Oil  Co.  on  the  site  of  the  old  Oklahoma 
Star  well,  bought  out  by  the  aforesaid  company,  was  only  a  small  gas 
well,  as  was  the  well  of  Hill  Petroleum  Corpn.  in  the  southeast  corner 
of  section  33.  Fortuna  No.  3,  in  section  35,  township  6  north;  range  10 
west,  missed  the  sand  but  is  drilling  deeper;  while  Fortuna  No.  4,  in 
the  center  of  section  6,  township  5  north,  range  9  west,  only  had  a  showing 
and  is  likewise  preparing  to  drill  deeper.  These  facts  indicate  consider- 
able irregularity  in  the  group  of  sands.  Several  wells  are  now  being 
drilled. 

STRATIGEAPHY 

The  formations  at  the  surface  appear  to  be  entirely  of  Permian  age, 
being  designated  technically  as  the  Enid,  Elaine  and  Woodward  forma- 
tions. The  vertical  section  of  the  outcropping  beds  covers  a  stratigraphic 
range  of  about  300  ft.  (91  m.).  In  this  section,  two  members  demand 
principal  consideration;  the  Whitehorse  sandstone  and  the  Cyril 
gypsum  bed. 

CYRIL  GYPSUM  BED 

The  most  persistent  formation  in  the  field  is  the  Cyril  gypsum,  which 
ranges  from  20  to  80  ft.  (6  to  24  m.)  in  thickness.  It  is  believed  to  under- 
lie the  Whitehorse  sandstone  of  northern  Oklahoma  and  here  overlies 
a  great  mass  of  generally  gray  sandstones  that  m'ght  be  supposed  to  be 
Pennsylvanian,  but  which  are  nevertheless  Permian  in  age.  In  southern 
Caddo  County,  this  gypsum  bed  is  thought  to  be  practically  synony- 
mous with  the  Blaine  formation.  There  is  no  sign  of  division  into  three 
gypsum  beds  as  in  central  Oklahoma. 


FREDERICK  G.  CLAPP  159 

FORMATIONS  OVERLYING  THE  CYRIL  GYPSUM 

The  strata  directly  overlying  the  principal  gypsum  bed  are  classified 
as  Whitehorse  sandstone  of  the  Woodward  formation,  the  intermediate 
Dog  Creek  shales  of  the  Oklahoma  Geological  Survey  being  generally 
absent.  Quite  outside  the  limits  of  the  field,  however,  are  great  masses  of 
red  shale  which  may  belong  in  the  overlying  Greer  formation. 

The  best  sections  of  the  uppermost  strata  are  visible  south  of  Cyril 
and  on  the  north  slopes  of  Keechi  Hills,  where  deeply  cut  ravines  inter- 
sect the  surface  and  expose  the  beds  throughout  a  thickness  of  more  than 
100  ft.  These  are  found  to  be  mainly  red  sandstones  and  red  sandy  shales, 
regularly  or  irregularly  stratified,  that  in  some  places  north  of  Keechi 
Hills  are  so  confused  with  recent  dune  sands  as  to  raise  the  question 
whether  they  too  may  not  have  been  wind-deposited. 

In  the  vicinity  of  Wichita  Mountains,  strong  winds  are  almost  con- 
stant and  sometimes  fill  the  air  with  such  clouds  of  dust  and  sand  as  to 
simulate  a  desert  sand  storm.  In  some  sections  these  winds  have  piled 
the  sand  into  considerable  hills;  for  instance,  over  considerable  areas  5  to 
10  mi.  southeast  of  Cement  and  also  1  to  5  mi.  north  of  that  town,  form- 
ing a  belt  parallel  with  and  north  of  Keechi  Hills.  In  this  belt  these 
generally  prevalent  southwest  winds  have  piled  up  the  sands  so  that  few 
rock  exposures  are  now  visible;  and  beyond  the  impression  of  a  synclinal 
or  homoclinal  slope,  little  can  be  learned.  Just  where  the  Permian  sands 
end  and  where  the  recent  dune  sands  and  sandstones  begin  in  these 
areas  is  hard  to  determine  in  most  cases. 

Overlying  the  red  sandstones  are  great  thicknesses  of  red  shales  and 
shaley  sandstones,  such  as  constitute  most  of  the  Permian  series  of  western 
Oklahoma. 

FORMATIONS  UNDERLYING  THE  CYRIL  GYPSUM 

The  Enid  formation  is  a  name  applied  by  the  Oklahoma  Geological 
Survey  to  the  lowermost  1500  ft.  (457  m.)  of  Permian  red  beds  up  to  the 
base  of  the  lowest  heavy  gypsum;  therefore,  in  the  Cement  field,  it  in- 
cludes all  strata  up  to  the  base  of  the  Cyril  gypsum.  So  far  as  the  Cement 
field  proper  is  concerned,  the  Enid  consists  of  massive  gray  sandstones 
of  great  hardness  and  persistence  with  overlying  red  sandstones;  but  few 
shales  have  been  found.  The  base  of  the  Permian  series  is  thought  to  lie 
about  2700  ft.  from  the  surface  but  some  geologists  place  it  at  1700  ft. 
Beyond  the  east  end  of  the  field,  a  gypsum  bed,  generally  only  about  2  ft. 
thick,  outcrops  in  a  few  places;  and  gypsiferous  sandstones  occur  in  the 
Enid  formation  in  many  localities. 

GEOLOGICAL  STRUCTURE 

The  geological  structure  of  the  Cement  field  is  better  known  and  more 
easily  determinable  than  that  of  any  other  known  dome  in  the  Permian 
series.  Only  at  its  east  end  is  there  any  considerable  difference  of  opin- 


160 


GEOLOGY   OF   CEMENT   OIL   FIELD 


ion  as  to  details.  It  is  an  excellent  anticline,  or  elongated  double  dome, 
on  which  the  zone  of  closure  appears  to  be  approximately  13  mi.  (21  km.) 
long  and  from  lj^  to  3  mi.  wide.  The  Cyril  gypsum  bed,  on  the  basis 
of  which  the  structure  contour  lines  of  the  accompanying  map  are  drawn, 
rises  from  the  center  of  the  Cyril  syncline,  1  mi.  south  of  Cyril,  at  an 
elevation  of  less  than  1350  ft.,  to  an  eroded  position  of  more  than  1650  ft. 
above  the  east  end  of  [the  main  Keechi  Hills,  3J£  mi._north  of  Cyril. 


R  IOW 


R9W 


R  8  W 


•OILINWCLL  LESS  THHUtMfttTOU? 

SHOHOF6ASINWELL  LCSS  THAN  2000  FEET  DEEP 
DRY  HOLE  I  ESS  THAN  ZOOO  FEET  DEEP 

•   OIL  WELL  IH2WO-FEETOKHJP  OF  SANDS 

LAKE  GAS  WELL  IN  i300-Ff.F.TGPOUP  OF  SANDS 
SMALL  MS  WELL  IN  Z300-FECT  GROUP  OF  SANDS 

O   WELLS  DP/LL/NO  Off  RIO  BUIL  T 

OW  IMP-FEET  CROUP  OF  SA 


s  wan 


PELO 


MAP  OF  CEMENT  OIL  FIELDS 

Ccrdc/o  County, Oklahoma. 


RIOW 


R9  W 


R8W 


FIG.  1. — GEOLOGICAL  STRUCTURE'AND  DISTRIBUTION  OP  WELLS  IN  CEMENT  FIELD. 
CONTOUR  LINES  ARE  ON  THE  BASIS  OF  THE  CYRIL  GYPSUM  BED.  CONTOUR  INTERVAL 
50  FEET. 

Descending  the  north  side  of  the  anticline,  the  gypsum  drops  below  1400 
ft.  (426  m.)  in  a  distance  of  2  mi.  (3  km.) .  West  the  axis  plunges  to  about 
1450  ft.,  6  mi.  north-northwest  of  the  apex,  and  to  1300  ft.  on  its  eastern 
end;  the  amplitude  of  closure  is  apparently  about  200  feet.  Although 
the  main  apex  of  the  anticline  is  situated  3J^  mi.  west  of  Cement,  a 
subsidiary  dome  with  an  apex  above  1550  ft.  centers  1  mi.  east  of  that 
village. 

In  the  eastern  end  of  the  anticline,  the  horizon  of  the  main  gypsum 
bed  appears  to  descend  to  below  1300  ft.,  and  northeast  it  drops  below 
1200  ft.  between  Ninnekah  and  Chickasha,  and  is  believed  to  go  much 
deeper;  but  the  exact  correlations  and  amount  of  descent  are  disputed  by 
gome  geologists. 

COMPARISON  WITH  OTHER  FIELDS 

When  comparing  the  geological  structure  of  the  Cement  field  with 
that  of  other  fields  in  southern  Oklahoma,  we  must  acknowledge  that 


FREDERICK   G.    CLAPP  161 

its  prospects  appear  excellent.  So  far  as  known  it  appears  to  be  more 
symmetrical  than  the  Healdton  field;  but  a  buried  mountain  range  may 
just  as  naturally  exist  beneath  the  Cement  field  as  at  Healdton.  The 
general  trend  of  the  Cement  field  corresponds  with  that  of  the  Healdton, 
Burkburnett,  Fox,  Two-Four,  Velma,  Loco,  and  other  less  thoroughly 
developed  fields.  While  the  general  geological  structure  and  attitude  of 
the  formations  are  rather  similar  to  those  in  the  Kilgore  field,  which  is 
being  developed  in  the  extreme  southeastern  corner  of  Grady  County  and 
in  the  adjacent  edge  of  Stephens  County,  the  trend  of  the  Kilgore  field 
is,  however,  north  and  south,  in  contradistinction  tojfchat  of  the  Cement 
field,  which  is  nearly  east  and  west.  &tf 

Correlations  with  the  Duncan,  Healdton,  Loco,  Wheeler,  and  other 
southern  Oklahoma  and  northern  Texas  fields  are  difficult;  but  we  have 
some  data,  and  estimate  that  the  Fortuna — or  principal  producing  group 
of  sands — may  be  identical  ^with  the  principal  gas  sand  of  the  Graham- 
Fox  field.  On  this  basis  we  might  expect  the  deep  new  sands  of  that  field 
at  about  3400  ft.;  but  in  the  only  deep  well  in  the  Cement  field  it  has  not 
been  struck  at  that  depth. 

ATTEMPTED  PREDICTIONS  RELATIVE  TO  POSITIONS  OP  DEEP  SANDS 

In  connection  with  studies  made  in  Carter,  Stephens,  and  adjoining 
counties,  the  writer  has  had  occasion  to  collect,  compile,  and  plot  many 
well  logs.  Since  these  logs,  when  compared  carefully  with  those  in  the 
Cement,  Kilgore,  Fox,  Graham,  and  Walters  fields,  give  certain  light  on 
geological  conditions  previously  unknown  and  since  this  information 
may  be  of  value  in  the  Cement  field,  it  is  given  herewith. 

The  wells  referred  to  as  being  the  deepest  or  nearly  deepest  in  their 
respective  fields  are  Prosperity  No.  1  in  Cement  field,  Magnolia  No.  1 
in  Walters  field,  a  well  of  the  Kirk  Oil  Co.  (which  produced  36,000,000 
cu.  ft.  per  day  of  gas)  in  Graham  field,  and  Pierce  No.  2  of  the  Oklahoma- 
Fox  Oil  Co.  in  the  so-called  Oklahoma-Fox  field.  These  wells  will  be 
referred  to  here  as  the  Prosperity,  Magnolia,  Graham  and  Oklahoma- 
Fox  wells,  respectively.  Many  logs  of  the  Cement  Oklahoma-Fox 
fields  and  of  the  Santa  Fe  No.  1  of  the  Kilgore  field  have  also  been  studied 
in  attempting  correlations. 

It  must  be  acknowledged  that  the  results  are  far  from  satisfactory, 
on  account  of  the  variable  nature  of  the  red-bed  formations,  the  uncon- 
formity at  the  top  of  the  Pennsylvanian  series,  and  the  personal  equa- 
tion in  the  case  of  records  kept  by  different  drillers  with  differing  degrees 
of  care.  There  are,  however,  several  sandstones,  limestones,  and  shale 
beds  of  enough  persistence  and  definite  characteristics  that  some  sort  of 
correlations  have  been  arrived  at  which,  although  not  positive,  are  definite 
enough  to  give  certain  ideas  in  the  nature  of  predictions.  The  informa- 

VOL.  LXV. 11. 


162  GEOLOGY   OF   CEMENT   OIL   FIELD 

tion  given  should  be  accepted  in  this  spirit,  rather  than  as  an  absolutely 
certain  exposition  of  what  will  be  found  by  deeper  drilling. 

First,  it  is  barely  possible  that  the  Prosperity  and  Fortuna  No.  5  wells 
of  Cement  field  passed  through  the  horizon  of  the  Magnolia  2150-ft. 
sand  of  the  Duncan  field  at  about  2550  ft.  without  finding  it.  It  is 
much  more  probable,  however,  that  the  horizon  of  the  Magnolia  sand  was 
passed  in  the  Prosperity  well  at  about  2700  ft. 

In  the  early  days  of  the  development  of  Cement  field,  we  had  no  basis 
by  which  to  predict  the  position  of  the  top  of  the  Pennsylvanian  series  of 
rocks  or  the  position  of  the  Healdton  group  of  sands,  because  the  records 
of  wells  in  the  Healdton  field  were  too  discordant  and  the  unconformities 
of  the  buried  "Healdton  Hills"  are  too  enormous  to  allow  of  deep-lying 
correlations.  Now,  however,  we  have  the  log  of  Pierce  Nos.  1  and  2  of 
Oklahoma-Fox  Oil  Co.  in  section  7,  township  2  south,  range  2  west  in 
northern  Carter  County.  These  wells  have  gone  to  a  greater  depth  than 
others  in  the  region,  the  producing  sands  being  apparently  about  1000ft. 
below  the  producing  sands  in  the  Graham  and  Fox  gas  fields.  One  of 
these  deep  sands  has  produced  over  100  bbl.  per  day  of  oil  into  the  pipe 
line.  The  oil  is  of  low  grade  but  will  presumably  be  lighter  in  fields 
farther  from  the  Arbuckle  Mountains.  The  sand  is  a  thick  one  and  is 
considered  as  about  the  stratigraphic  position  of  the  best  oil  sands  in  that 
part  of  Oklahoma.  At  least  three  possibilities  exist : 

1.  The  Fortuna  sand  of  the  Cement  field  may  have  been  penetrated 
at  about  600  ft.  (182  m.)  in  the  Graham  field  and  missed  entirely  in  the 
Oklahoma-Fox  field.     In  this  case  the  Magnolia  sand  exists  at  about 
1000  ft.  at  Graham.     Then  the  horizon  of  the  Graham  gas  sand  (1480 
ft.)  should  lie  at  about  3200  ft.  in  the  Cement  field,  and  the  Oklahoma- 
Fox  sands  at  about  4200  ft. 

2.  The  Fortuna  sand  may  lie  at  1000  ft.  (304  m.)  at  Graham,  and  have 
been  missed  in  the  Oklahoma-Fox  wells.     In  this  case  the  Magnolia 
sand  is  the  same  as  the  Graham  gas  sand  (1480  ft.)  and  probably  the  same 
as  the  1540-ft.  sand  in  the  Oklahoma-Fox  wells.     Then  the  Oklahoma- 
Fox  deep  sands  will  be  found   presumably  at  about  3200  ft.  in  the 
Magnolia  well  and  about  3700  ft.  in  the  Cement  field. 

3.  The  Fortuna  sand  may  be  equivalent  to  the  big  gas  sand  in  the 
Graham  and  Fox  fields  (1480  ft.)  and  to  the  1540-ft.  sand  in  the  Okla- 
homa-Fox wells.     In  this  case,  the  Magnolia  sand  was  missed  around 
1900  ft.  in  the  last-mentioned  wells,  and  the  horizon  of  the  Oklahoma- 
Fox  deep  sands  may  be  expected  at  about  3400  ft.  in  the  Cement  field. 
This  depth  has  now  been  passed  by  Fortuna  No.  3  well  in  shale. 

Whichever  hypothesis  is  correct,  there  seems  no  possibility  of  finding 
the  Healdton  or  Oklahoma-Fox  sands  at  Cement  at  less  than  3400  ft., 
and  they  may  be  as  deep  as  4200  ft.  The  Oklahoma-Fox  sands  are  con- 
sidered as  constituting  a  part  of  the  "Healdton  group,"  which  are  often 


FREDERICK    G.    CLAPP  163 

referred  to  informally  but  do  not  correlate  satisfactorily  in  records  of 
wells  in  the  Healdton  field,  on  account  of  considerable  unconformities 
existing  there. 

These  attempted  correlations  open  a  wide  field  for  thought  and  con- 
sideration. Our  next  starting  point  must  be  that  the  Magnolia  sand  of 
the  Duncan  field  appears  to  be  at  about  the  top  of  the  Pennsylvania 
series  (bottom  of  the  Permian  "Red  Beds")  above  which  it  is  not  usual 
to  expect  oil  in  large  quantity.  In  the  great  fields  of  Wichita  County, 
Tex.,  and  to  some  extent  in  the  Healdton  field,  large  producers  were  found 
in  sands  above  this  horizon;  but  these  were,  and  are  generally,  believed  to 
be  seepages  from  lower  sands.  Because  the  red  beds  are  not  capable  of 
having  originated  oil  in  themselves,  geologists  generally  agree  that  oil 
contained  in  them  has  risen  from  formations  of  the  Pennsylvanian  series. 
This  is  the  main  reason  for  confidence  that  the  main  sands  at  Cement  lie 
below  anything  yet  encountered. 

Operators  in  Cement  field  should  not  allow  themselves  to  become  dis- 
couraged over  the  outlook;  they  should  bear  in  mind  the  following  facts: 

1.  Since  large  gas  wells  and  excellent  showings  of  oil  have  been  found 
both  at  Cement  and  Kilgore  in  sands  of  the  Permian  series,  which  are  not 
normally  oil  bearing,  we  may  expect  something  better  in  deeper  sands 
lying  in  the  Pennsylvanian  series. 

2.  It  will  not  be  necessary  to  go  to  the  full  3200  or  4200  ft.  throughout 
the  Cement  field,  as  several  sands  are  generally  present  in  the  Permian 
and  Pennsylvanian  and  some  of  these  are  productive  at  shallower  depths. 

3.  It  is  decidedly  possible  that  the  Fortuna  group  of  sands  may  be 
more  productive  than  usual  somewhere  in  the  field,  as  is  the  case  with 
Permian  sands  in  the  Healdton  and  Wichita  County  fields. 

4.  The  finding  of  still  shallower  sands  in  the  so-called  Two-Four  field 
in  western  Carter  County  and  southeastern  Stephens  County  proves  that 
the  sands  of  the  Permian  formations  are  very  irregular,  and  some  of  these 
lenticular  sands  may  hold  oil  somewhere  in  the  Cement  field. 

5.  It  is  possible,  and  even  probable,  that  the  Keechi  Hills,  which  are 
coincident  with  the  Cement  field,  overlie  a  buried  mountain  range,  as 
the  Healdton  field  overlies  the  buried  "Healdton  Hills."     In  such  case 
the    conditions    at   a  depth  generally  become  irregular  and  unusual 
and  numerous  new  sands  occur,  expanding  the  field  laterally  in  these 
"stray"  sands. 

6.  Deep  drilling  will  not  be  a  permanent  obstacle  to  the  development 
of    the   deep   sands,  as  wells  have  been  drilled  economically  in  this 
field  by  the  rotary  process.     The  cost  of  4000-ft.  wells  in  the  future  will 
be  less  than  the  cost  of  existing  wells.     New  wells  started  in  the  field 
should  be  drilled  with  a  rotary  prepared  to  go  to  4500  ft.  if  necessary. 

The  one  fact  that  appears  undoubted  is  that  a  considerable  series  of 
oil  sands  should  be  expected  below  the  Cement,  Kilgore,  and  other  fields 
and  some  of  these  may  be  expected  to  produce  oil  at  Cement. 


164  GEOLOGY  OF   CEMENT  OIL   FIELD 

Most  of  the  statements  here  made  apply  also  to  the  Kilgore  field. 
Although  correlations  and  predictions  are  only  of  relative  value,  it  is 
believed  that  since  the  sands  in  these  fields  are  deep  and  that  both  of 
them  are  surrounded  by  deep  synclines,  the  chances  are  good  for  large 
productions  as  soon  as  the  difficulties  in  deep  drilling  have  been  overcome. 

CONCLUDING  STATEMENTS 

The  foregoing  is  an  exposition  of  conditions,  developments,  and  prob- 
abilities in  Cement  field  according  to  the  information  and  belief  of  the 
writer.  As  in  all  fields  in  the  course  of  development,  it  is  not  practicable 
for  any  person  other  than  a  resident  geologist  to  have  all  the  facts  at  hand, 
therefore  some  details  may  be  in  error.  Especially  is  it  thought  some 
geologists  may  have  further  light  on  the  probabilities  and  predicted 
depths  of  deeper  sands. 


IRVINE   OIL   DISTRICT,   KENTUCKY  165 


Irvine  Oil  District,  Kentucky 

BY  STUART  ST.  CLAIB,*  M.  S.,  E.  M.,  CHICAGO,  ILL. 
(Chicago  Meeting,  September,  1919) 

IN  VIEW  of  the  great  interest  shown  in  the  oil  possibilities  of  Kentucky, 
one  is  impressed  with  the  paucity  of  reliable  literature  on  the  oil  fields  of 
the  state.  A  few  brief  reports  by  the  Federal  and  State  Geological 
Surveys  are  about  the  only  reliable  data  available.  When  the  estimated 
production  figures,  for  1918,  are  published  by  the  U.  S.  Geological  Survey, 
they  will  show  a  revival  of  the  oil  industry  in  the  Blue  Grass  State  during 
the  past  half  decade.  There  will  also  be  an  increase  in  the  production  for 
1919  and  1920,  at  least.  Although  as  an  oil-producing  state  Kentucky  is 
small,  compared  with  some  of  the  other  oil  states,  the  present  production 
and  the  area  of  undrilled  proved  territory  is  large  enough  to  classify  it  as 
one  of  the  important  oil  states  of  the  Union.  This  paper  will  be  confined 
to  the  Irvine  District  and  the  immediately  adjoining  areas  which  have 
been  prospected  with  varying  success.  The  Corniferous  limestone  or 
Irvine  sand  is  the  oil-producing  formation  in  the  area  discussed. 

In  my  divisional  nomenclature,  the  Irvine  District  includes  the  Irvine 
field,  which  extends  from  the  town  of  Irvine  eastward  toward  Campton; 
the  Big  Sinking  area,  which  joins  and  lies  to  the  south  of  the  eastern 
part  of  the  Irvine  field;  the  Beattyville  area,  which  lies  to  the  north 
and  northeast  of  the  town  of  that  name  and  joins  the  Big  Sinking  area; 
and  the  Ross  Creek  pool,  which  lies  to  the  southwest  of  the  big  production 
and  across  the  Kentucky  River.  Except  for  the  Ross  Creek  pool,  the 
main  producing  area  is  bounded  on  the  east  by  the  L.  &  E.  R.  R.  and  on  the 
west  and  south  by  the  Irvine  Branch  of  the  L.  &  N.  R.  R.  Winchester  and 
Lexington  form  the  gateways  and  Torrent  on  the  east,  Irvine  on  the  west, 
and  Beattyville  on  the  south  are  the  principle  entrances  to  the  main  fields. 
Evelyn,  on  the  L.  &  N.  R.  R.,  south  of  Irvine,  is  the  point  of  entrance  to 
the  Ross  Creek  area. 

GEOLOGY 

The  geology  of  the  Irvine  District  is  very  simple.  The  rock  forma- 
tions with  which  the  oil  man  should  acquaint  himself  lie  between  the 
lower  measures  of  the  Pennsylvanian  sandstones  and  shales  and  the  Devon- 
ian or  Corniferous  limestone,  or  Irvine  formation.  Only  a  very  brief 
description  of  these  formations  will  be  given,  as  they  have  been  described 
fully  by  E.  W.  Shaw.1 

1  U.  S.  Geol.  Survey  Bull.  661d. 


166  IRVINE    OIL   DISTRICT,    KENTUCKY 

Capping  the  hills,  and  forming  a  rim-rock  over  the  eastern  part  of  the 
Irvine  field,  the  Big  Sinking,  and  Ross  Creek  areas,  is  a  cliff-forming 
sandstone  above  which  are  yellowish-gray  and  dark  colored  shales  with 
irregular  sandstone  and  conglomerate  members,  and  also  some  valuable 
coal  beds.  Below  are  dark  colored  shales,  with  irregular  thin  sandstones, 
with  a  thickness  up  to  about  50  ft.  (15.24  m.).  Underlying  these  is  the 
Big  Lime  of  the  driller,  or  Newman  or  St.  Louis  limestone.  It  is  typically 
exposed  along  the  L.  &  N.  R.  R.  from  a  point  south  of  Irvine  nearly 
to  Heidelberg  and  in  this  district  varies  in  thickness  between  100  ft. 
(30.48  m.)  and  125  ft.  (38.1  m.).  The  underlying  Waverly  formation  is 
composed  chiefly  of  a  bluish-green  shale  and  has  an  average  thickness  of 
about  450  ft.  (137.16  m.).  The  Waverly  and  the  underlying  Black 
Shale  formation  increase  in  thickness  eastward  and  southeastward  from 
the  Irvine  field.  The  Berea  sand  is  found  in  the  lower  part  of  the 
Waverly  formation  in  the  eastern  part  of  Kentucky  and  in  adjoining  oil 
sections  of  West  Virginia  and  Ohio.  The  Devonian,  or  Chattanooga, 
black  shale  varies  in  thickness  between  120  ft.  (36.57  m.)  and  170  ft. 
(51.81  mj  in  the  Irvine  District.  The  base  of  the  formation  in  most 
places  is  a  white  shale,  or  fireclay  as  it  is  locally  called,  which  varies  up 
to  20  ft.  (6.09  m.)  in  thickness.  In  some  localities,  brown  shale  from  a 
few  feet  to  25  ft.  (7.6  m.)  in  thickness  underlies  this  and  directly 
overlies  the  Corniferous  limestone,  which  is  the  Irvine  sand  of  Kentucky. 
This  formation  is  a  dolomitic  limestone,  sandy  at  a  few  irregular 
strata,  and  contains  chert  in  varying  amounts.  Porous  beds,  irregular 
in  their  continuity,  are  the  oil  sands  of  the  formation.  The  outcrop 
at  Irvine  is  brown  in  color  and  about  8  ft.  (2.43  m.)  thick,  but  eastward 
the  formation  thickens  rapidly,  attaining  about  100  ft.  (30.48  m.)  at  the 
eastern  and  southern  edges  of  the  main  producing  field.  In  Wolfe  County, 
near  the  Breathitt  county  line,  the  formation  is  approximately  175  ft. 
(53.34  m.)  thick.  Underlying  the  Devonian  are  the  Silurian  shales  and 
interbedded  limestones  and  the  Ordovician  limestones,  one  of  which  is, 
perhaps,  in  part  the  equivalent  of  the  Trenton. 

The  Irvine  District  is  affected  by  the  Cincinnati  geanticline,  which 
extends  in  a  general  north-and-south  direction,  and  the  Chestnut  Ridge 
uplift,  the  axis  of  which  crosses  Kentucky  in  an  east-and-west  direction. 
All  beds  dip  away  from  the  former  structure,  thereby  making  the  general 
dip  in  the  Irvine  District  southeast.  The  Chestnut  Ridge  uplift  has 
been  described,  by  Gardner,  as  extending  from  Pennsylvania  through 
West  Virginia,  Kentucky,  and  southern  Illinois.  This  is  a  general  dis- 
turbance which  has  been  of  paramount  importance  in  the  formation  of 
some  of  the  principal  oil  structures  in  this  district.  The  northern  boun- 
dary of  the  Irvine  field  is  marked  by  the  Irvine  fault,  which  is  part 
of  the  Chestnut  Ridge  disturbance.  The  general  position  of  this  fault- 
ing is  shown  by  Shaw.  Most  of  the  anticlines  of  the  district  closely 


STUART  ST.   CLAIB  167 

parallel  the  direction  of  this  faulting.  An  eastward  extension  (includ- 
ing the  Ashley  pool,  the  production  near  Zachariah,  and  to  the  east  of 
Torrent)  is  similar  structurally  to  the  Irvine  field.  The  Camp  ton  ex- 
tension was  reported  on  by  Munn.2 

From  his  observations,  the  writer  is  led  to  believe  that  there  are 
anticlinal  structures  of  two  ages  in  this  part  of  Kentucky  and  very 
probably  in  other  parts  also.  The  main  structures  apparently  are  the 
younger,  have  a  general  east-and-west  trend,  and  were  formed  by  the 
Chestnut  Ridge  uplift,  which  was  probably  completed  in  the  Tertiary 
period.  The  general  trend  of  the  older  structures  is  north-and-south, 
but  the  writer  hesitates  to  venture  a  statement  regarding  their  age  as  he 
has  not  had  the  opportunity  of  studying  all  the  facts  that  may  bear  upon 
this  problem.  Some  evidently  antedate  the  last  period  of  general  base- 
levelling  of  the  region  and  are  probably  associated  with  the  Cincinnati 
uplift.  These  conclusions  have  been  reached  from  a  study  of  the  rela- 
tion between  present  topographic  features  and  the  structure.  The 
localization  of  some  of  the  large  producing  areas  may  be  due,  in  part,  to 
the  intersection  of  the  younger  with  the  older  structures. 

OCCURRENCE  OF  OIL 

Oil  men  who  have  had  experience  in  a  field  where  the  oil  is  found  in  a 
limestone  will  appreciate  the  eccentricities  of  sand  condition  encountered 
in  development  work  in  Kentucky.  In  localities  where  the  limestone  is 
hard  and  tightly  cemented,  the  whole  formation  may  be  barren.  Tight 
sand  conditions  may  be  encountered  in  the  center  of  an  area  with  pro- 
ducing wells  on  all  sides  and  but  a  few  hundred  feet  distant.  Such  a 
condition  is  most  unfortunate  when  encountered  in  a  prospect  well  in  un- 
developed territory,  as  the  operator  may  prematurely  abandon  the  area. 
Drilling  has  shown  parts  of  the  Corniferous  limestone  to  be  generally 
porous  over  the  area  described  here.  Usually  a  porous  bed  of  variable 
thickness,  from  a  few  feet  to  10  ft.  (3.04  m.)  or  more,  occurs  directly 
under  a  hard  limestone  cap-rock.  Under  favorable  structural  conditions, 
this  porous  bed  may  be  entirely  filled  with  oil,  and  under  less  favorable 
structure  part  or  all  of  it  may  contain  salt  water.  Over  part  of  the  Irvine 
District  only  one  pay  sand  is  found  but  in  some  localities  two  or  more 
with  a  little,  though  in  many  wells  without  any,  intervening  salt  water. 
In  some  areas  abundant  salt  water  may  be  encountered  under  the  cap- 
rock,  where  the  first  pay  sand  should  be  found,  and  must  be  cased  off 
before  lower  pay  sands  can  be  drilled  into.  In  fact,  each  locality  pre- 
sents varying  conditions,  so  an  intimate  knowledge  of  the  field  should 
be  acquired  in  order  that  the  operator  may  know  how  to  handle 
the  problems  confronting  him  in  the  development  of  his  property. 

2  M.  J.  Munn:  U.  S.  Geol  Survey  Bull  471a. 


168  IRVINE    OIL   DISTRICT,    KENTUCKY 

In  general,  the  oil  accumulation  has  taken  place  under  anticlinal 
conditions.  In  the  producing  areas,  all  folds  and  well-defined  terrace 
structures  have  been  productive  and  salt-water  wells  have  been  the 
result  of  drilling  in  the  less  favorable  places.  Exception  may  be  taken 
to  this  statement  by  some  geologists  when  applied  to  the  Big  Sinking 
area,  but  when  other  factors  governing  oil  accumulation  in  this  pool, 
which  factors  will  be  mentioned  later,  are  considered  in  association  with 
the  anticlinal  theory,  this  general  statement  will  be  found  to  cover  the 
case. 

Only  a  generalized  description  of  the  Big  Sinking  area  will  be  given 
here,  as  a  complete  report  on  the  oil  pools  of  Lee  County  is  being  con- 
templated. From  certain  deductions  that  will  be  given  regarding  this 
field,  the  reader  may  appreciate  the  writer's  reasons  for  having  strongly 
recommended  the  Big  Sinking  Creek  area  as  early  as  the  spring  of  1917, 
when  the  nearest  drilling  was  some  miles  distant.  At  that  time  the 
writer  outlined  on  the  map  of  a  prominent  Kentucky  oil  producer  the 
probable  western  boundary  of  the  Sinking  Creek  area  as  being  the  divide 
between  Little  Sinking  Creek  and  Billy's  Fork  of  Millers  Creek,  and  the 
probable  eastern  limit  as  the  divide  between  Hell  Creek  and  Walkers 
Creek.  So  far,  nothing  of  importance  has  been  developed  beyond 
these  bounds  close  enough  to  be  classified  as  part  of  the  Sinking  Creek 
area. 

From  what  has  been  said  regarding  the  anticlinal  occurrence  of  oil 
in  the  Irvine  District,  the  reader  has  probably  formed  the  opinion  that 
drilling  on  such  structure  outside  of  the  present  proved  area  should  also 
result  in  favorable  strikes.  However,  experience  has  shown  the  oppo- 
site results.  Wells  located  near  Beattyville,  farther  south  in  Owsley 
County,  in  southern  Lee  County,  in  eastern  Lee  County  north  of  Tallega, 
in  Breathitt,  Wolfe,  and  Elliott  counties,  all  located  on  well-defined 
anticlinal  structures,  have  struck  only  shows  of  oil.  In  the  wells 
closest  to  the  producing  fields,  salt  water  was  encountered;  in  those 
farther  away,  the  Corniferous  limestone  was  hard  and,  in  most  cases, 
practically  dry. 

BIG  SINKING  POOL 

The  structure  of  the  Big  Sinking  area  is  not  complicated.  The  re- 
gional monoclinal  dip,  which  is  southeast,  is  crossed  by  several  very  low 
folds,  the  axes  of  which  are  in  a  general  east-and-west  direction.  The 
resultant  would  be  plunging  anticlines  with  a  general  southeast-by-east 
trend.  Minor  irregularities  have  produced  terraces.  In  conjunction 
with  this  type  of  structure,  a  broad  low  fold  extends  in  a  general  north- 
and-south  direction  and  definitely  outlines  the  western  and  eastern 
limits  of  the  Big  Sinking  pool.  The  axis  of  this  fold  roughly  follows 
Sinking  Creek  from  Bald  Rock  Fork  northward  and  the  more  pro- 


STUART   ST.    GLAIR  169 

ductive  part  of  the  pool  is  along  the  crest  and  on  the  southeast  flank 
of  the  fold  with  the  most  productive  points  determined  by  the  east-and- 
west  folds. 

The  number  of  pay  sands  and  their  total  thickness  is  variable  in  the 
Big  Sinking  pool.  As  many  as  three  sands,  with  a  thickness  of  40  ft. 
(12.19  m.)  have  been  reported  but  in  some  places  5  ft.  (1.5  m.)  will  cover 
all  the  actual  pay  sand  encountered.  Probably  15  to  20  ft.  (4.57  to 
6.09  m.)  is  an  average  for  the  more  productive  parts  of  the  pool.  In 
general,  the  pay  sand  is  very  porous,  although  in  short  distances  it  may 
tighten  up  materially.  The  best  sand  condition  for  quick  recovery  ap- 
parently lies  along  the  crest  and  the  southeast  flank  of  the  north-and- 
south  fold.  Westward  from  this  fold,  the  sand  changes  rapidly.  East- 
ward, the  change  is  more  gradual,  but  with  the  increasing  depth,  due 
to  the  regional  dip,  the  sand  becomes  tighter  and  the  pay  is  not  so  thick 
nor  uniform.  However,  wells  in  the  tighter  sand,  although  the  produc- 
tion is  smaller  pef  day,  will  be  longer  lived  than  the  wells  in  the  porous 
sand.  The  writer  has  estimated  that  from  the  very  porous  sand  as  much 
as  1000  bbl.,  and  in  a  few  selected  spots  1200  bbl.,  to  the  acre-foot  of 
actual  pay  sand  will  be  produced.  This  amount  will  decrease  to  500  bbl. 
and  probably  as  low  as  200  bbl.  to  the  acre-foot  as  the  tighter  sand  areas 
are  approached. 

The  thickness  of  pay  sand  reported  by  various  owners  and  lease  men 
is  often  misleading  or  in  error.  In  most  cases,  the  thickness  of  the  true 
pay  sand  is  much  less  than  it  is  thought  to  be  when  the  well  is  being 
drilled.  Therefore,  in  making  computations,  the  thickness  of  actual  pay 
sand  should  be  carefully  determined  or  the  error  in  the  calculated  pro- 
duction per  acre  will  be  large.  This  rough  method  should  be  used  only 
when  no  production  data  on  the  property  or  adjoining  properties  are 
available  from  which  decline  and  future-production  curves  can  be 
constructed. 

The  writer  has  been  frequently  asked  why  the  oil  is  found,  through- 
out the  Big  Sinking  area,  on  the  higher  and  in  the  lower  structural  posi- 
tions. It  is  quite  evident  that  this  condition  is  due  to  water  pressure, 
chiefly  from  the  south  and  southeast,  which  is  behind  a  sufficient  body  of 
oil  to  cause  the  sand  to  be  filled  with  oil  over  the  entire  area,  thereby 
forming  one  large  pool  in  which  nearly  every  location  is  proved.  Salt 
water  will  encroach  upon  the  field  from  the  south  and  the  wells  in  that 
part  of  the  field  and  in  the  lower  structural  positions  will  be  affected 
first. 

EXTENSION  OF  EASTERN  FIELDS 

The  writer's  personal  experience  in  the  Kentucky  oil  fields  has  led  to 
some  deductions  that  may  throw  some  light  on  the  conditions  described, 
and  which  may  be  of  value  in  prospecting  the  Corniferous  limestone  or 


170  IRVINE   OIL  DISTRICT,    KENTUCKY 

Irvine  sand  in  the  eastern  part  of  the  state.  The  area  under  which  the 
Irvine  sand  will  be  productive  of  oil  in  commercial  quantities  is  dependent 
on  three  primary  conditions,  which  are  listed  in  the  order  of  their  impor- 
tance: (1)  Distance  from  the  outcrop  of  the  Irvine  sand  and  from  the 
major  faults.  (2)  Porous  or  non-porous  character  of  the  Corniferous 
limestone.  (3)  Geologic  structure.  The  writer  will  probably  be  criti- 
cized for  making  the  second  condition  less  important  than  the  first,  but 
in  this  field  the  porous  or  non-porous  character  of  the  oil  formation  is 
dependent  almost  entirely  on  the  distance  from  the  outcrop,  and  espe- 
cially from  the  major  faults  along  which  meteoric  water  is  able  to  reach 
the  Corniferous  limestone.  It  will  be  remembered  that  such  a  system  of 
faulting  extends  along  the  northern  boundary  of  the  Irvine  field  and  on 
the  eastward  occupying  a  similar  relation  to  the  Campton  and  Cannel 
City  fields.  Water  circulating  through  certain  beds  of  the  Corniferous 
limestone  has  dissolved  some  of  the  mineral  matter  and  left  the  rock 
porous.  The  irregularity  in  the  thicknesses  of  these  porous  beds  indicates 
that  solution  has  taken  place  under  non-uniform  conditions  of  underground 
circulation.  The  distance  to  which  this  circulation  of  meteoric  water  has 
taken  place  from  the  outcrop  or  fault  will  mark  the  area  of  continuous 
porous  formation,  which  may  contain  either  oil  or  salt  water  according 
to  structural  conditions,  and  will  mark  the  limit  of  the  area  that  has  been 
unaffected  by  water  circulation  and  in  which  the  Corniferous  limestone 
will  generally  be  tight  and  hard.  The  water  in  the  Irvine  sand,  being 
heavier  than  the  oil,  will  occupy  a  position  farthest  down  the  regional 
dip  and  will  be  dammed  back  by  increasingly  less  porous  beds.  This 
would  form  what  we  may  term  a  monoclinal  trough  produced  by  dif- 
ferential cementation  of  the  limestone.  Obviously  then,  a  well  drilled 
on  the  crest  of  an  anticline  near  the  lower  limit  of  this  water  area  would 
encounter  water  and  not  oil  in  the  Irvine  sand.  The  position  of  the  oil 
on  the  regional  monocline  would  depend  on  the  amount  of  water  in  the 
trough.  As  stated  before,  it  is  the  writer's  belief  that  this  pressure  of 
salt  water  to  the  south  of  the  Big  Sinking  area,  together  with  very  porous 
rock  conditions  underlying  the  Big  Sinking  area,  is  the  explanation  for 
the  unusually  large  concentration  of  oil  in  this  field  and  may  explain  the 
presence  of  oil-saturated  sand  strata  in  both  higher  and  lower  structural 
positions  in  the  Big  Sinking  pool.  The  pressure  that  causes  flowing  wells 
is  water  pressure  and  gas  pressure  combined.  Some  water  has  been  en- 
countered at  the  southern  edge  of  this  pool  although  none  has  yet  been 
found  in  the  main  part  of  the  pool. 

Outside  of  the  large  area  that  has  been  affected  by  circulating  waters, 
there  may  be  small  areas  where  the  Corniferous  limestone  has  sufficient 
porosity,  either  primary  or  through  recrystallization  or  dolomitization, 
or  where  minor  faults  have  allowed  some  meteoric  water  to  reach  the 
Corniferous  limestone  and  dissolve  some  of  it,  thus  producing  porosity  in 


STUART   ST.    CLAIR 


171 


the  rock,  to  allow  small  accumulations  of  oil.  Chance  drilling  may 
strike  small  pools  of  this  class,  which  may  be  found  on  anticlines  or  in 
lower  structural  positions.  Tests,  however,  should  be  made  on  the  most 
favorable  structures  that  can  be  found.  No  wells  in  this  category  of  any 
importance  have  yet  been  struck  unless  the  Little  Frozen  Creek  produc- 
tion is  extended  beyond  its  present  limits. 


^  Paris 


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urchcad 


(/^Raglcntl 
^''Pool 


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i'-'.v';  Menefee 

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C^M  §S  BcattyoitU    L&aloney     Oil  Pool  Litile  **»* 

.  «?«$  —^roi^— ,/.    .p  ^c*.«» 


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S  atitm 
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0  McKee 


SOtu 

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FlG.   1  OlL  POOLS  PRODUCING  FROM  THE  IRVINE  SAND. 

Roughly,  the  probable  line  of  separation  of  the  possible  productive 
area  and  the  non-productive  area  for  the  Corniferous  limestone  may  be 
drawn.  Inside  this  line  proper  structural  conditions  are  necessary  for 
commercial  accumulations  of  oil.  The  line  should  run  along  the  east 
side  of  Ross  Creek  near  the  Lee  County  line  to  Kentucky  River;  then 
eastward  through  Heidelberg,  Beattyville,  and  Maloney;  then  north- 
eastward, probably  passing  close  to  Holly  Creek,  Wolfe  County;  then 
paralleling  and  closely  following  the  Campton-Cannel  City  anticline. 
This  line  is  shown  in  Fig.  1  as  the  limit  of  the  area  of  productive  Corni- 


172  IRVINE   OIL  DISTRICT,   KENTUCKY 

ferous  limestone.  The  approximate  position  of  the  Irvine  fault  and  the 
outcrop  of  the  Corniferous  or  Irvine  sand  are  also  shown  together  with 
the  oil  and  gas  pools  producing  from  the  Irvine  sand. 

If  the  theory  that  the  distance  from  the  outcrop  is  of  primary  impor- 
tance in  determining  whether  the  Corniferous  limestone  will  be  porous 
enough  for  oil  to  accumulate  in  is  correct,  in  areas  where  this  formation  is 
present  and  of  similar  character  to  what  it  is  in  the  Irvine  District,  and 
if  the  overlying  petroliferous  black  shale  is  present,  under  favorable 
structural  conditions  there  should  be  some  accumulation  of  oil  or  gas; 
provided  the  structure  is  far  enough  away  from  a  fault  of  any  magnitude, 
which  is  on  the  down-dip  side  of  the  structure,  to  allow  a  sufficient  area 
from  which  accumulation  may  come.  Reference  to  Fig.  1  will  show  that 
the  Menefee  gas  field,  the  Ragland  oil  field,  and  the  Station  Camp, 
Ross  Creek,  Buck  Creek,  and  Lanhart  oil  pools  are  not  far  from  the  out- 
crop of  the  Irvine  sand.  These  fields  are  located  on  structures  and, 
therefore,  other  small  fields  may  be  opened,  under  favorable  structural 
conditions,  within  a  restricted  distance  from  the  outcrop  of  the  Irvine 
sand.3 

ECONOMIC  CONDITIONS 

For  the  past  two  years,  Kentucky  has  enjoyed  a  great  oil  boom  and 
prices  for  acreage  have  gone  sky-rocketing  in  certain  parts  of  the  state, 
following  each  strike  of,  importance.  Probably  no  area  has  had  such  a 
quick  advance  in  speculative  prices  in  such  a  short  time  as  the  Big  Sinking 
area  in  Lee  County.  Two  years  ago,  the  Irvine  field  extending  north- 
eastward from  the  town  of  Irvine  to  Pilot  was  receiving  nearly  all  the 
attention  of  the  oil  men.  Acreage  along  Big  Sinking  Creek  was  selling 
for  a  very  small  bonus.  With  the  opening  of  the  Ashley  pool,  Pilot 
district,  the  price  of  acreage  began  to  advance  and  by  the  fall  of  1917, 
acreage  in  the  Big  Sinking  area  was  selling  from  $50  60  $100  per  acre. 
During  the  year  1918,  prices  advanced  to  $2000  and  $3000  per  acre, 
with  extra  royalties  attached,  in  some  cases.  On  such  high-priced  acre- 
age, flowing  wells  are  sometimes  drilled,  but  the  average  initial  produc- 
tion will  probably  be  between  100  and  300  bbl.  per  day.  The  writer 
knows  of  a  few  wells  that  produced  close  to  1000  bbl.  the  first  day  and 
another  that  flowed  24,000  bbl.  in  a  little  over  four  months.  Although 
these  are  the  exceptions,  there  are  many  wells  that  are  producing  far 
above  the  average. 

The  practice  of  additional  royalty  was  started  when  there  was  no 
valid  reason  for  such  action.  It  has  kept  many  strong,  conservative 
companies  out  of  the  field  and  has  brought  in  many  operators  who  had 

*  Since  this  article  was  written,  several  oil  wells  have  been  drilled  in  southeastern 
Menefee  County  on  a  well-defined  structure. 


STUART   ST.    GLAIR  173 

the  oil  business  to  learn  and  some  stock  companies  who  had  to  get 
production. 

The  Big  Sinking  area  is  a  remarkable  oil  pool.  The  depths  of  the 
wells  vary  from  800  to  1200  ft.  (243.8  to  365.7  m.),  dependent  on  the 
topography.  It  has  two,  and  in  some  places  three,  pay  sands  with  an 
aggregate  thickness  of  10  to  30  ft.  (3.04  to  9.14  m.).  Much  of  the  pay 
sand  is  very  porous  and  the  oil,  in  parts  of  the  field,  is  under  considerable 
pressure.  The  gravity  of  the  oil  is  around  40°  Baum6  and  the  gasoline 
content  above  30  per  cent.4  The  cost  of  drilling  and  equipping  a  well 
varies  from  $3000  to  $5000.  These  advantages,  however,  do  not  warrant 
the  payment  of  such  high  prices  for  acreage  and  additional  royalty  when 
the  average  size  of  the  initial  production  is  considered.  On  account  of 
the  porosity  of  the  pay  sands,  the  production  will  decline  rapidly  and  the 
average  life  of  the  wells  in  the  Big  Sinking  field  will  not  be  long. 

The  Big  Sinking  pool  is  so  young  and  in  the  older  Irvine  pool  such  poor 
records  of  production  were  kept  that  it  is  difficult  to  get  many  accurate 
figures  from  which  depletion  can  be  computed.  Some  leases  that  were 
located  on  favorable  geologic  structure  and  had  average  sand  conditions 
were  producing  about  10  per  cent,  as  much  oil  at  the  end  of  the  first 
year  as  they  were  producing  at  the  point  of  maximum  flush.  Others 
have  declined  considerably  more  where  the  wells  were  put  too  close 
together.  However,  a  few  of  the  properties  in  the  older  Irvine  field  have 
held  up  remarkably  well,  a  fact  that  may  be  due  to  a  thicker  pay  and 
tighter  sand,  or  inability  of  the  pipe  line  to  take  all  the  oil.  The  oil  sand 
in  the  best  parts  of  the  Big  Sinking  pool  is  so  porous  that  wells  should  not 
be  too  close  to  one  another.  One  well  to  five  acres  should  be  sufficient; 
but  on  many  leases  the  wells  are  300  ft.  (91.4  m.)  apart  and  not  infre- 
quently there  is  one  well  to  the  acre.  Under  such  conditions  the  wells 
must  decline  rapidly,  unless  there  is  an  unusually  thick  pay  sand. 

The  writer  has  estimated  that  on  properties  where  wells  are  properly 
spaced  and  where  there  is  an  average  thickness  of  pay  sand,  a  well  that  is 
continuously  pumped  would  be  producing  about  10  per  cent,  of  its  initial 
capacity  at  the  end  of  a  year.  Where  the  pipe  line  does  not  take  all  the 
oil  produced,  or  where  protracted  shut-downs  are  experienced,  these 
estimates  must  be  made  proportional  to  the  lengths  of  the  unpumped 
periods.  Further,  the  average  well,  which  will  have  an  average  thickness 
of  pay  sand,  in  the  very  porous  sand  areas  of  the  Big  Sinking  pool,  that 
is  pumped  regularly  to  its  capacity  will  probably  produce  as  much  in  the 
first  six  months  as  during  the  remainder  of  its  life.  In  tighter  sand  areas 
it  will  probably  take  a  year  to  produce  half  the  oil  under  regular  pumping 
conditions,  and  to  get  the  maximum  recovery  the  wells  should  be  spaced 


4  The  writer  has  been  informed  that  some  tests  have  shown  a  gravity  of  42°  Be". 
and  a  gasoline  content  of  45  per  cent. 


174  IRVINE   OIL   DISTRICT,    KENTUCKY 

closer  than  in  the  porous-sand  areas.  What  has  been  said  of  the  indi- 
vidual well  may  be  applied  collectively  to  a  lease.  Where  new  wells  are 
being  drilled  and  production  is  being  added  all  the  time,  the  decline  in  the 
producing  wells  is  not  as  noticeable  as  when  the  property  is  fully  devel- 
oped. Production  and  decline  records  of  wells  and  leases  should  be 
carefully  kept  so  that  the  owner  may  profit  by  the  depletion  allowance  for 
which  he  can  claim  exemption  from  taxation. 

A  company  purchased  a  small  lease  that  was  producing  and  only 
partly  drilled  up,  paying  at  a  specified  rate  per  barrel  of  production  that 
amounted  to  approximately  $30,000  per  acre.  With  a  very  porous  sand 
and  20  ft.  (6.09  m.)  of  pay  sand,  probably  15,000  to  20,000  bbl.  per  acre 
should  be  recovered,  if  the  pay  is  as  thick  as  claimed.  At  the  end  of 
about  five  months  of  regular  pumping  7000  bbl.  per  acre  was  removed, 
which  is  between  one-half  and  one-third  the  calculated  recoverable  oil. 
At  the  end  of  two  or  three  years,  the  property  will  be  practically  exhausted. 
A  small  profit  will  be  shown  on  the  investment  if  depletion  is  charged  off 
each  year  at  a  rate  commensurate  with  the  decline  of  the  property.  The 
importance  of  correct  estimates  of  depletion  of  properties  in  the  Big  Sink- 
ing pool  and  in  other  pools  of  similar  character  in  Kentucky  cannot  be 
too  forcibly  impressed  upon  the  operators. 

The  producing  area  north  and  northeast  of  Beattyville  is  but  a  south- 
ern extension  of  the  Big  Sinking  field  and  the  remarks  made  are  appli- 
cable to  it.  Drilling  is  a  little  deeper  and  the  wells  are  smaller,  but 
there  is  room  for  expansion  of  area.  Care,  however,  should  be  taken  in 
drilling  to  avoid  the  salt  water.  The  Ross  Creek  pool  is  the  Big  Sinking 
on  a  small  scale.  It  has  been  greatly  overdrilled  and  must,  necessarily, 
have  a  short  life.  The  area  is  rather  limited  but  there  are  possibilities 
for  a  small  extension  southward.  Prospects  for  a  few  smaller  areas  of 
production  in  this  general  region  are  good.5  The  Irvine  field  has  been 
quite  fully  exploited  and  only  drilling  up  of  proved  territory  remains. 
This  field  has  now  been  extended  eastward  several  miles  beyond  Torrent, 
the  eastern  entrance  to  the  producing  areas.  Efforts  to  carry  production 
north  of  the  fault  in  this  field  have  failed. 

Kentucky  was  a  poor-man's  field  during  the  early  stages  of  its  recent 
oil  development  and  many  have  made  comfortable  fortunes.  To  get 
acreage  anywhere  near  the  proved  fields  today  requires  capital.  Wild- 
cat acreage  can  be  gotten  cheap  but  the  chances  of  success  are  commen- 
surately  lessened.  There  are  opportunities  for  consolidation  today  that 
did  not  exist  a  short  time  ago.  Many  local  organizations  could  be 
handled  much  more  economically  and  efficiently  if  they  were  under  larger 

6  Since  this  article  was  written,  in  the  fall  of  1918,  a  pool  has  been  opened  on  Buck 
Creek,  Estill  Co.,  about  4  mi.  (6.4  km.)  north  of  Ross  Creek.  The  area  is  one  of  the 
prospects  referred  to  and  promises  to  furnish  a  number  of  small  producing  wells. 


STUAKT    ST.    CLAIR  175 

managements.  Conservation  is  a  pertinent  question;  mismanagement 
and  waste  can  be  seen  in  many  places  and  must  cause  injury  to  the  field. 
Considerable  gas,  which  should  be  rich  in  gasoline,  is  allowed  to  go  to 
waste  by  the  thousands  of  cubic  feet  per  day.  However,  the  field  is 
young  and  such  conditions  are  remedied  with  time. 

CONCLUSION 

The  object  of  this  paper  is  to  call  attention  to  the  probability  that  the 
area  of  production  from  the  Irvine  sand  in  eastern  Kentucky  is  a  function 
of  the  distance  from  the  outcrop  of  the  oil  formation  and  from  the  major 
faults.  The  results  of  many  wells  drilled  to  the  south,  southeast,  and 
east  of  the  producing  Irvine  sand  pools  uphold  this  theory.  However, 
the  writer  does  not  wish  to  discourage  prospecting  in  the  deeper  areas 
as  there  are  possibilities  of  opening  up  small,  isolated  pools.  Prospecting 
should  also  be  carried  on  with  a  view  to  opening  up  production  in  sands 
higher  than  the  Corniferous  limestone.  Southeast  and  east  of  the  Irvine 
District,  the  Berea,  the  Big  Injun,  and  sands  higher  than  the  Big  Lime 
may  be  found  to  contain  oil  in  commercial  quantities.  In  Knox,  Floyd, 
Magoffin,  and  Lawrence  counties,  there  has  been  small  production  from 
these  higher  sands  for  many  years.  A  number  of  wells  have  been  drilled 
below  the  Corniferous  limestone  in  the  Irvine  District,  but  no  oil 
formations  were  found.  Sands  are  reported  but  oil  shales  apparently  are 
absent.  The  possibility  of  finding  a  deeper  pay  sand  is  not  very  promising. 


176         GENETIC   PROBLEMS   AFFECTING   SEARCH   FOR   NEW   OIL  REGIONS 


Genetic  Problems  Affecting  Search  for  New  Oil  Regions 

BY  DAVID  WHITE,*  WASHINGTON,  D.  C. 
(New  York  Meeting,  February,  1920) 

IN  THESE  days,  when  detailed  investigations  of  stratigraphy,  structure, 
and  sand  conditions  so  frequently  result  in  the  discovery  of  new  oil  fields, 
and  applause  from  oil  companies  and  the  public,  geologists  do  well  to 
walk  humbly,  and  punctiliously  to  admit  that  the  geologic  principles 
controlling  the  distribution  of  oil  and  gas  have  as  yet  been  discovered 
only  in  part,  and  that  what  remains  yet  to  be  learned  is  probably  vastly 
more  than  what  is  already  known.  The  few  experiments  already  at- 
tempted have  been  fragmentary,  and  somewhat  desultory,  and  however 
positive  each  of  us  may  be  with  respect  to  certain  theoretical  conclusions, 
many  of  the  fundamental  questions  as  to  the  origin  and  mode  of  occur- 
rence of  petroleum  are  subject  to  radical  disagreement.  Of  the  chemical 
changes  attending  the  generation  of  petroleum  from  organic  matter, 
little  is  actually  known.  Most  of  the  postulated  formulas  are  liable  to 
be  misleading,  through  ignorance  of  essential  factors.  Open-minded- 
ness  is  therefore  a  prime  essential  at  the  present  stage  of  our  science. 
Nevertheless,  adopting  the  hypothesis  that  oil  originates  in  some  man- 
ner fundamentally  connected  with  the  organic  theory,  and  in  possible 
departure  from  such  open-mindedness,  the  writer  will  pay  no  attention  to 
the  so-called  inorganic  theory,  since  every  attempt  to  apply  this  theory 
to  the  study  of  old  oil  fields,  or  to  the  discovery  of  new  ones,  affords 
cumulative  evidence  of  its  inadequacy. 

In  this  paper,  some  of  the  factors  affecting  the  occurrence  of  petro- 
leum that  the  writer  believes  worthy  of  consideration  by  the  prospector 
for  oil  in  any  new  region  will  be  discussed.  Some  of  these,  which  are 
less  generally  understood,  will  be  considered  somewhat  in  detail.  Other 
points,  the  significance  of  which  cannot  now  be  determined,  require  more 
field  study,  and  for  that  reason  are  here  brought  to  the  attention  of  the 
field  geologist.  On  the  other  hand,  certain  theoretical  points  which  do  not 
bear  especially  on  the  oil  possibilities  of  a  new  region  will  be  given  little 
or  no  attention.  The  main  topics  that  will  be  discussed  are:  (1)  suffi- 
ciency of  carbonaceous  detritus  and  residues  in  the  oil-forming  rocks;  (2) 
stage  of  carbonization  of  the  organic  matter  in  the  oil-bearing  formations; 
(3)  folding  of  the  strata;  (4)  thickness  of  sedimentary  formations;  (5) 
conditions  of  deposition. 

*  Chief  Geologist,  U.  S.  Geological  Survey. 


DAVID  WHITE  177 

SUFFICIENCY  OF  CARBONACEOUS  DEBRIS  AND  RESIDUES  IN 
THE  OIL-FORMING  ROCKS 

Most  oil  and  gas  geologists  agree  that  in  those  formations  in  which  oil 
is  found  there  must  be  sufficient  organic  matter  genetically  to  account  as 
mother  substance  for  the  oil,  which  is  believed  to  have  escaped  from  its 
mother  rock  into  some  suitable  and  accessible  reservoir  rock  where  it  is 
confined  beneath  impervious  strata.  However,  very  little  seems  to  be 
known  as  to  the  requisite  quantity  of  mother  substance  or  as  to  the  maxi- 
mum distance  at  which  this  substance  may  be  situated  from  the  reservoir. 

Most  geologists  assume  that  this  mother  substance  is  carbonaceous, 
but  others  hold  that  recognizable  carbonaceous  debris  or  visible  residues 
are  not  necessarily  present.  "Bituminous"  or  other  carbonaceous  shales 
and  milestones  are  almost  invariably  searched  for  because,  seemingly 
with  good  reason,  such  deposits  are  regarded  as  the  principal  materials 
from  which  petroleum  may  be  generated;  certainly  they  are  the  rocks 
from  which  oils  nearest  to  typical  petroleum  may  be  artificially  produced 
by  distillation.  As  shown  by  Orton  and  others,  similar  carbonaceous 
matter  adequate  for  supplying  oil  and  gas  may  be  found  in  most  regions 
disseminated  through  the  rock  or  concentrated  in  certain  layers;  it  is 
present  in  ample  amounts  even  in  less  distinctly  carbonaceous  shales  and 
limestones,  and  in  some  sandstones,  and  there  seems  no  room  for  doubt 
that  oil  in  commercial  amounts  has  been  derived  from  such  deposits. 
Most  dark  limestones,  sandstones,  and  shales,  as  well  as  ordinary  black 
shales,  owe  their  dark  tones  to  the  presence  of  carbonaceous  residues, 
which  are  easily  recognized  under  the  microscope.  Yet  it  remains  to  be 
seen  how  much  of  such  organic  matter  is  requisite,  as  a  minimum — 
probably,  in  reality,  an  average  minimum.  Circumstantial  evidence — 
the  conditions  actually  presented  in  certain  oil  fields — seems  to  indicate 
that  the  carbonaceous  matter  need  compose  but  a  very  small  percentage 
of  a  supposed  mother  formation,  if  the  matter  is  of  the  right  sort,  and  if 
other  requisite  conditions  are  fulfilled,  and  that  a  very  great  thickness  of 
the  mother  formation  is  not  indispensable.  In  general,  however,  our 
most  productive  oil  deposits  are  found  in  districts  containing  formations 
in  which  there  is  evidence  of  abundant  life,  with  ample  vegetal 
matter.  That  only  smaller  productions  are  found  in  districts  con- 
taining little  carbonaceous  matter  may  prove  to  be  a  rule  with 
numerous  exceptions. 

In  the  search  for  oil  in  regions  containing  thick  series  of  strata  so 
barren  of  carbonaceous  matter  as  the  "Red  Beds"  of  New  Mexico, 
Arizona,  and  the  northern  Rocky  Mountain  States,  or  as  the  Jurassic  of 
Utah,  southwestern  Colorado,  northern  Arizona,  and  northwestern  New 
Mexico,  or  as  the  Newark  formation  of  the  Connecticut  Valley  and  Penn- 
sylvania, the  question  as  to  the  quantity  of  organic  matter  appears,  at  the 

VOL.  LXV. 12. 


178        GENETIC   PROBLEMS   AFFECTING   SEARCH   FOR   NEW   OIL   REGIONS 

present  moment,  to  be  somewhat  insistent.  As  bearing  in  a  practical 
way  on  this  problem,  the  demonstrated  occurrence  of  oil  in  the  Conemaugh 
of  the  Appalachian  Basin,  in  the  Embar  and  associated  beds  of  Wyoming, 
in  the  "Red  Beds"  of  north  Texas  and  Oklahoma,  and  in  small  amounts 
in  red  beds  near  Roswell,  New  Mex.,  may  be  cited.  It  must  be  admit- 
ted, however,  that  the  Conemaugh  carries  thin  coals  and  carbonaceous 
shales;  that  the  Permian  reds  of  Oklahoma  and  Texas  contain  rare  beds  of 
coal  and  carbonaceous  shales,  usually  of  limited  horizontal  extent;  and 
that  disseminated  carbonaceous  matter,  in  aggregate  amounts  larger 
than  at  first  thought,  may  be  present  in  portions  of  the  Embar  and  in 
intercalated  shales  or  sandstones  in  the  "Red  Beds"  of  New  Mexico. 
On  the  other  hand,  it  is  a  question  whether,  in  at  least  some  of  these 
cases,  the  oil  has  not  migrated  upward  from  more  carbonaceous  beds  in 
relatively  remote,  underlying  formations;  or  even  whether  the  oil  has 
not  migrated  downward.  The  presence  of  other  oil  sands  lying  in  more 
richly  carbonaceous  formations,  at  different  and  sometimes  great  depths 
beneath  the  "Red  Beds"  sands  in  the  Appalachian  Basin  and  in  the  Mid- 
Continent  field,  lends  weight  to  the  supposition  that  in  some  cases  the  oil 
has  migrated  upward  instead  of  originating  in  the  "  Red  Beds  "  themselves. 
If  the  oil  in  the  latter  regions  has  ascended  into  the  "Red  Beds,"  deeper 
sands  should  be  tested  in  the  possibly  less  forbidding  shales  beneath  the 
Embar  of  Wyoming  and  the  Abo  of  New  Mexico,  and  beds  to  the  base 
of  the  Percha  will  be  explored  in  southern  New  Mexico,  if  the  Percha  is 
present  and  not  too  greatly  altered. 

A.  W.  McCoy,  who  has  had  most  excellent  opportunities  for  studying 
the  composition  of  the  beds  penetrated  by  the  drill  in  the  Mid-Continent 
field,  points  out1  the  presence  of  ample  carbonaceous  material,  including 
oil  shale,  intimately  associated  with  the  Bartlesville  sand  in  northern 
Oklahoma,  and  suggests  that  closer  inspection  will  reveal  the  presence  of 
sufficient  mother  substance  in  close  proximity  to  the  oil  sands  in  other 
regions.  The  discovery,  somewhere,  of  oil  in  a  series  of  distinctly  non- 
carbonaceous  "Red  Beds,"  directly  underlain  by  metamorphic  rocks  or 
igneous  masses,  with  no  possible  source  in  nearby  unaltered  sediments, 
would  have  an  important  bearing  on  this  problem,  and  should  be  recorded ; 
drilling  under  such  conditions,  however,  will  probably  be  done  with  great 
hesitation.  The  argument  that  oil  in  the  above-mentioned  "Red  Beds" 
has  migrated  downward  suggests  the  inquiry  whether  the  associated  gas 
also  gravitated.  Certainly,  if  oil  has  not  been  generated  in  beds  which, 
on  casual  view,  appear  to  contain  very  little  organic  matter,  the  petro- 
leum in  some  of  our  sands  must  have  migrated  across  many  hundred 
feet  of  strata  before  finding  hospitable  storage  in  its  present  reservoirs. 

lJnl.Geol.  (1919)27,  252. 


DAVID    WHITE  179 

The  term  "organic  matter"  should  be  restricted  to  carbonaceous 
debris  and  residues,  as  distinguished  from  non-carbonaceous  mineral 
deposits  of  organic  origin,  such  as  shells,  diatoms,  etc.,  which  may  now  be 
devoid  of  any  associated  hydrocarbons.  Such  mineral  deposits  do  not, 
I  believe,  serve  as  mother  substance  of  oil,  although,  when  porous,  they 
may  offer  excellent  storage.  In  many,  perhaps  most  cases,  however,  lime- 
stones contain  some  matter  that  is  strictly  organic  and  may  have  been 
mother  substance.  Impure,  especially  argillaceous,  bituminous  lime- 
stones should  well  serve  the  purpose  of  mother  rock,  and  have  un- 
doubtedly done  so. 

The  question  as  to  whether  oil  may  not  have  been  generated  in  the 
biochemical  stage  at  the  time  of  the  decay  and  deposition  of  the  organ- 
isms, such  as  mollusca  or  diatoms,  as  believed  by  Stuart  and  many  other 
oil  geologists,  is  a  debatable  point  germane  to  this  subject,  but  will  be 
considered  in  connection  with  the  influence  of  diastrophic  movements. 
The  discovery  of  oil  pools  in  a  great  thickness  of  strata  actually  barren 
of  carbonaceous  or  so-called  bituminous  matter,  but  containing  lime- 
stones largely  of  " organic"  origin,  and  underlain  by  metamorphic  or 
igneous  basements,  would  give  force  to  this  theory. 

STAGE  OF  CARBONIZATION  OF  THE  ORGANIC  MATTER  IN  THE  OIL-BEARING 

FORMATIONS 

A  study  of  the  incipient  regional  metamorphism  of  carbonaceous 
deposits  in  the  coal  and  oil  fields  of  the  United  States  and  other  countries 
shows  that  no  commercially  important  oil  fields  have  yet  been  discovered 
in  any  area  where  the  fuel  ratios  of  the  coals,  occurring  in  the  formations  in 
which  oil  is  sought  or  in  overlying  formations,  exceeds  2.3.  The  progres- 
sive devolatilization  by  which  the  coals  in  any  region  or  formation  have 
been  transformed  from  peats  to  lignites,  bituminous  coals,  etc.,  and 
finally  to  graphite,  is  the  first  indication  of  incipient  metamorphism2  of 
the  rocks  of  the  area.  The  proximate  analysis  of  the  coal  or  coaly  deposits, 
as  the  writer  has  shown,3  is  a  sort  of  "ultra-violet"  method  of  observing 
this  initial  stage  of  regional  metamorphism  of  the  ordinary  type.  Other 
attending  criteria  include  the  stages  of  dehydration,  consolidation  or 
lithification,  development  of  jointing  and  cleavage,  and,  in  due  time, 
schistosity  and  mineralization. 

More  observations  and  tests  are  necessary  to  fix  more  exactly  the 
stage  of  regional  alteration  beyond  which  commercial  oil  pools,  though 

2  In  this  transformation  the  mass  of  organic  debris  (coal  or  coaly  matter)  is  altered 
both  in  chemical  composition  and  physical  characters.     In  other  words,  technically, 
it  is  genuine  metamorphism. 

3  Jnl  Wash.  Acad.  Sci.  (1915)  6;  Bull  Geol.  Soc.  Amer.  (1917)  28,  727-734- 


180       GENETIC   PROBLEMS   AFFECTING   SEARCH   FOR   NEW   OIL   REGIONS 

formerly  present,  will  not  have  survived,  but  it  is  probable  that  the 
limit  falls,  in  general,  slightly  lower  than  the  point  at  which  coals  of  the 
ordinary  bituminous  type  show  a  fuel  ratio  of  2.2,  or  68  per  cent,  of  fixed 
carbon  in  the  pure  coal;  it  may  approach  nearer  the  ratio  of  2.0,  or  66 
per  cent,  fixed  carbon.  Coals  verging  toward  the  sapropolic  type,  such 
as  are  believed  by  many  to  approach  more  closely  the  typical  mother 
substance  of  oil,  are  more  fatty  and  accordingly  richer  in  hydrogen  and 
lower  in  fixed  carbon  (pure  coal  basis)  than  the  other  types,  until,  in  the 
course  of  alteration  by  geologic  processes,  they  approach  the  above  limit, 
when  the  volatile  matter  seems  to  disappear  rapidly.  At  the  semi- 
bituminous  stage  (fuel  ratio  3.0,  fixed  carbon  75  per  cent.),  their  carboni- 
zation is  approximately  on  a  parity  with  typical  bituminous  coal. 

It  is  important  that,  in  a  new  region  under  consideration  as  to  oil 
possibilities,  every  precaution  be  taken  to  ascertain  whether  the  alteration 
of  the  rocks,  as  indicated  by  the  stage  of  carbonization  of  the  carbonaceous 
deposits,  has  not  gone  so  far  as  to  preclude  the  survival  of  oil  in  commer- 
cial amounts.  As  I  have  shown  in  the  papers  already  cited,  drilling  in 
regions  of  greater  metamorphism  will  find  only  gas  or  mere  showings  of 
"white  oil " — approximately  kerosene — generally  little  more  than  samples, 
and  nowhere  in  commercial  amount.  This  principle  appears  to  be  proved 
by  thousands  of  tests  in  the  Appalachian  field,  in  the  Mid-Continent 
region,  and  in  other  parts  of  the  world. 

Oil  in  commercial  amounts  should  not  be  expected  in  the  Devonian 
of  east-central  and  southeastern  New  York  and  eastern  Pennsylvania; 
in  the  Paleozoic  regions  of  Georgia;  in  the  Arkansas  coal  field;4  nor  in 
those  areas  of  northeastern  Kentucky,  of  eastern  Tennessee,  of  Alabama, 
of  the  Paleozoic  region  in  southeastern  Oklahoma,  and  portions  of  New 
Mexico,  Colorado,  Montana,  Utah,  and  Washington,  as  well  as  of  Penn- 
sylvania, Maryland,  Virginia  and  West  Virginia,  where  the  regional 
carbonization  has  passed  the  stated  limit.  The  Utica,  Genessee, 
Hudson,  Ohio,  Chattanooga,  and  Woodford  shales  are  splendid  de- 
positories of  mother  substance,  but  it  is  futile  to  search  for  oil  in  the 
associated  "sands"  in  regions  where  the  organic  matter  of  these  shales 
is  too  far  altered. 

It  is  unfortunate  that  so  little  attention  has  been  given  to  this  factor 
of  control  of  the  distribution  of  oil,  and  so  little  systematic  effort  has  been 
made  to  secure  such  evidence  as  might  have  been  gained.  Data  are 
needed,  for  example,  as  to  the  carbonization  of  the  organic  matter  in  the 


4  Over  300  holes  have  been  drilled  in  the  Arkansas  coal  field  with  but  a  showing  of 
"white  oil"  in  a  single  instance,  although,  as  in  Pennsylvania,  West  Virginia  and 
other  areas,  gas  may  be  present  in  commercial  amounts  in  anticlines,  where  the  car- 
bonization has  progressed  too  far  for  the  survival  of  oil  pools.  An  asphaltic  dyke  at 
Mena,  in  the  altered  region  of  Arkansas,  has  been  anthracitized. 


DAVID   WHITE  181 

Percha  (Devonian)  shale  and  the  Magdalena  limestone  and  Sandia 
formations  in  portions  of  New  Mexico,5  for  the  information  concerns  not 
only  the  probability  of  finding  oil  pools  in  or  adjacent  to  these  forma- 
tions, but  also  the  problem  as  to  the  source  of  oil  that  may  be  found  in 
the  overlying  Red  Beds.  It  is  known  that  the  coals  of  the  Mesa  Verde, 
in  portions  of  the  Trinidad,  Crested  Buttes,  and  Durango  coal  fields, 
approach,  if  they  do  not  pass,  the  fuel-ratio  limit,  but  the  boundaries  of 
the  areas  in  which  oil  should  not  be  expected  in  this  or  the  underlying 
formations  have  not  been  determined  for  lack  of  sufficient  and  properly 
distributed  coal  analyses.  The  high  probability  that  the  abundant 
organic  debris  in  formations  like  the  Mancos  and  Graneros,  and  the  still 
older  formations  beneath  the  Mesa  Verde,  have  been  still  more  altered 
must  not  be  overlooked  in  any  search  for  oil  deep  below  the  coals  in  these 
regions  of  relatively  high  carbonization. 

Also,  in  the  lower  Saline  River  Valley,  in  southeastern  Illinois,  where 
the  carbonization  advancing  toward  the  south  approaches  the  oil  limit, 
some  uncertainty  will  attend  exploration  for  oil  in  anticlines  of  the  Miss- 
issippian,  Devonian,  and  Trenton,  which  furnish  oil  in  other  parts  of 
the  state.  The  degree  of  carbonization  of  organic  deposits  in  the  exposed 
beds,  and  the  probably  greater  alteration  of  the  underlying  beds,  deserve 
further  consideration,  wherever  the  data  are  procurable,  in  the  regions 
of  some  of  the  anticlines  located  in  the  direction  (southwest)  of  advancing 
carbonization  in  Montana;  and  it  should  not  be  ignored  in  the  vicinities 
of  the  coal  fields  near  Sunnyside,  Utah,  and  in  Washington  and  Oregon. 

Disregarding  contact  metamorphism,  which  from  the  present  stand- 
point is  unimportant,  it  is  probable  that  regional  alteration  in  much  of 
the  Newark  formation  of  the  Atlantic  States  has  advanced  too  far  to 
encourage  the  driller,  even  where  the  series  has  great  thickness,  contains 
ample  carbonaceous  matter,  and  is  not  too  closely  folded.  If  found  to  be 
not  too  far  altered,  it  should,  where  sufficiently  thick,  be  reviewed  by  the 
oil  geologist.  Reliable  information,  if  it  can  practicably  be  obtained, 
is  to  be  desired,  as  to  the  stage  of  alteration  of  the  Upper  Paleozoic 
in  portions  of  Montana,  Utah,  and  Arizona,  though  it  is  possible  that 
in  some  areas  inferences  based  only  on  cleavage,  induration,  incipient 
schistosity,  and  mineralization  (not  contact  alteration),  can  be  drawn. 
In  many  instances,  valuable  deductions  may  be  based  on  distillation 
tests  of  oil  shales  or  other  richly  bituminous  shales  which,  if  far 
devolatilized,  will  yield  little  oil,  though  containing  much  carbon. 

In  passing,  it  should  be  noted  that:  (a)  local,  slight  variations  of 
carbonization  are  not  to  be  ignored,  for  they  are  to  be  expected,  especially 


6  The  coal  of  the  lower  Pennsylvania!!  appears  to  be  too  far  altered  in  the  Pecos 
Valley,  about  10  miles  above  New  Pecos,  and  samples  from  Bernalillo  County  cast 
suspicion  on  the  same  formation  in  that  county. 


182       GENETIC   PROBLEMS   AFFECTING   SEARCH   FOR   NEW   OIL   REGIONS 

in  closely  folded  and  faulted  areas;  (6)  in  general,  carbonization  advances 
downward,  according  to  the  law  of  Hilt,8  so  that  the  fuel  ratios  of  coals  in 
underlying  formations  will,  in  most  cases,  be  higher  than  in  the  exposed 
formations,  thus  offering  no  hope  of  getting  oil  at  greater  depths  where 
the  regional  alteration  of  the  exposed  rocks  is  too  great;  (c)  the  carboni- 
zation rule  applies  only  to  areas  in  which  the  alteration  is  regional,  not 
contact  metamorphism ;  (d)  the  fuel  ratios  are  typically  based  on  coals 
or  coaly  deposits  of  the  so-called  bituminous  group,  and  may  be  satis- 
factorily determined  in  coaly  streaks,  in  very  earthy  and  bony  coals, 
and  in  shales  containing  great  amounts  of  organic  matter,  though  it  is 
not  yet  proved  that  they  can  be  determined  in  shales  carrying  but  small 
percentages  of  carbonaceous  matter.  Attempts  to  determine  the  per- 
centage of  fixed  carbon  in  the  organic  matter  of  ordinary  carbonaceous 
shales  have  not  yet  been  wholly  successful,  but  experiments  are  now  in 
progress  with  the  object  of  learning  the  minimum  of  carbonaceous  matter 
that  may  be  reliably  subjected  to  proximate  analysis  in  the  average 
carbonaceous  shale.  If  methods  can  be  devised  for  successfully  ascer- 
taining the  fuel  ratio  in  the  organic  matter  of  even  moderately  carbonace- 
ous shales,  criteria  of  the  greatest  value  will  be  available  to  the  driller. 

As  bearing  upon  the  grade  of  oil  that  may  be  expected  in  a  new 
region,  attention  may  again  be  called  to  the  observation  that,  in  general, 
the  oils  in  regions  of  relatively  high,  but  not  too  high,  carbonization  are 
characteristically  of  the  highest  grade,  that  is,  of  low  gravity;  while  in 
regions  of  less  carbonization  the  oils  average  higher  in  gravity.  Going 
still  further,  as  the  writer  has  elsewhere  pointed  out,  the  oils  found  in 
regions  of  low-rank  coals,  such  as  lignites  (brown  coals),  are  also  character- 
istically, though  not  without  exception,  lowest  in  rank,  notwithstanding 
the  lack  of  satisfactory  explanation  of  the  fact,  on  what  may  at  the  present 
moment  be  considered  a  reasonable  chemical  basis.  The  true  explana- 
tion may  come  from  the  thorough  application  of  experimental  physics 
and  physical  chemistry  to  the  oil  problem. 

The  causes  of  carbonization  (alteration)  of  the  organic  debris  and  resi- 
dues in  sedimentary  formations  have  been  more  fully  discussed  in  my 
previous  papers,  but  will  be  briefly  reviewed  in  the  following  section. 

FOLDING  OF  STRATA 

Folding  of  the  strata,  or  the  development  of  structure,  is  almost 
universally  regarded  as  an  essential  feature  of  any  oil  region.  The 
migration  and  "gravitational"  segregation  of  oil,  gas,  and  water  are 
commonly  supposed  to  be  connected  with  the  existence,  if  not 
indeed  with  the  origin,  of  folds,  and  in  particular  with  minor  local 

«U.  S.  Bureau  of  Mines  Bull.  38  (1913),  125. 


DAVID   WHITE  183 

anticlines  and  domes.  Therefore,  folding  is  always  looked  for  and 
analyzed  in  detail. 

However,  to  what  extent  and  through  what  processes  folding  operates 
as  a  cause,  or  a  means,  or,  on  the  other  hand,  whether  it  is  to  be  regarded 
only  as  an  effect  or  a  mere  indication,  is  yet  to  be  shown.  Most  of  us 
hold  that  folds  facilitate  the  segregation  and  localize  the  distribution  of 
oil  and  gas  pools,7  and  are  therefore  of  great  consequence  in  the  search 
for  new  oil  fields;  contrasted  with  this  view,  folding  seems  to  be  regarded 
by  some  geologists  mainly  as  an  effect  of  questionable  importance. 

One  of  the  most  thoughtful  advocates  of  the  operation  of  folding  as  a 
cause  of  the  migration  of  oil  and  gas  is  Marcel  R.  Daly,8  who  starts  with 
the  assumption  that  the  oil  already  exists,  presumably  from  the  date  of 
deposition  of  the  terrane,  disseminated  in  the  clays,  sands,  etc.  in  the 
form  of  minute  spherical  globules  between  the  mineral  particles.  Under 
increasing  loading  by  deposition  of  superincumbent  strata,  the  argillace- 
ous and  organic  deposits  are  compressed  and  the  water,  oil,  and  gas  are 
gradually  squeezed  out  of  the  compacting  deposits,  moving  in  the  direc- 
tion of  least  resistance  into  the  less  compressible  sandy  beds  and  sand- 
stones. Coalescence  of  the  globules  and  concentration  of  the  liquids 
proceed  en  route.  In  the  sandstone,  separation  of  the  water,  oil,  and 
gas  tend  to  go  forward  according  to  the  size  of  the  pore  spaces,  the  water, 
with  its  greater  capillary  tension,  tending  to  occupy  the  fine-grained 
portions  and  forcing  the  oil  and  gas  into  the  larger  voids.  Horizontal 
stresses  of  diastrophism,  causing  new  and  greater  differential  compression 
of  the  beds,  produce  waves  of  unequal  compression  and,  overcoming 
friction,  drive  the  water  and  hydrocarbons  into  the  zones  of  less  pressure, 
some  of  which  are  the  forerunners  of  anticlines  as  buckling  proceeds, 
the  tops  of  the  anticlines  offering  zones  of  least  compression,  while  the 
bottoms  of  the  synclines  are  most  squeezed. 

The  important  point  of  Daly's  presentation  is  the  function  of  loading 
and  thrust  pressure  in  causing  the  escape  of  the  water  and  oil  from  its 
matrix  into  the  sands,  and  in  overcoming  capillary  resistance  to  further 
migration  into  reservoirs  and  anticlines.  It  is  hoped  that  this  paper  will 
bring  partial  support  to  some  of  Mr.  Daly's  conclusions. 

In  previous  discussions9  of  the  features  common  to  the  genesis  of  coal 
and  of  oil,  the  writer  has  insistently  pointed  out  that  the  evolution  of  each 
is  brought  about  through  the  common  agency  of  dynamic  forces — mainly 
horizontal  stresses — acting  on  loaded  strata  and  causing  the  progressive 

7  Preliminary  compilations  by  K.  C.  Heald  indicate  that  over  88  per  cent,  of  the 
anticlines  and  domes  in  the  Osage  Nation  are  oil-bearing,  as  compared  with  about 
15  per  cent,  of  the  synclines. 

8  Trans.  (1916)  66,  733-753. 

•  Jnl  Wash.  Acad.  Sci.  (1915)  6;  U.  S.  Bureau  of  Mines  Bull  38  (1913)  91; 
Bull  Geol.  Soc.  Amer.  (1917)  28,  727. 


184   GENETIC  PROBLEMS  AFFECTING  SEARCH  FOR  NEW  OIL  REGIONS 

devolatilization  of  the  organic  debris  and  residual  products  buried  in  the 
sedimentary  deposits.  Both  coal  and  oil  are  products  of  alteration,  by 
geologic  processes,  of  organic  matter  not  only  similar,  but,  at  least,  in  part, 
identical  in  composition.  Coal  consists  of  the  mass  or  stratum  of  rela- 
tively pure  organic  debris,  including  the  residual  solid  hydrocarbons 
left  in  the  process  of  transformation  from  peat,  or  its  genetic 
equivalent  (deposited  under  different  conditions),  to  graphite.  Oil, 
on  the  other  hand,  is  a  volatile  product  of  this  natural  "distillation" 
by  the  same  agencies,  of  the  organic  debris  and  residues  buried  in 
the  sedimentary  deposits. 

The  transformations  or  geochemical  changes  are  intimately  associated 
with,  if  they  are  not  actually  caused  by  mainly  horizontal  stresses,  under 
loading,  with  consequent  molecular  displacement,  and  some  incidentally 
generated  heat.  The  temperature  developed  during  the  process  was 
probably  very  moderate,  and  almost  certainly  was  not  great  enough  to 
distil  the  organic  matter  at  slight  pressures.10  There  is  generally  but 
little  trace  of  alteration  of  the  rock  except  progressive  dehydration,  com- 
pression, and  lithification  in  the  earlier  stages,  with  some  sericitization; 
the  latter  can,  however,  hardly  be  attributed  to  hydro  thermal  action,11 
since  there  is  no  evidence  of  the  percolation  of  magmatic  waters.  De- 
formation of  crystals  has  not  yet  been  observed,  except  in  sands  of  regions 
where  the  carbonization  is  approaching  anthracitization,  in  which  case  a 
change  to  quartzite,  and  some  deformation  of  quartz  grains,  may  be 
noted,  as  well  as  occasional  thin  platy  cleavage,  probably  representing 
incipient  schistosity.  As  the  regional  alteration  approaches  the  gra- 
phitic stage,  mineralization  and  considerable  deformation  of  the  rock 
grains,  including  pebbles,  may  locally  be  noted.  In  short,  the  trans- 
formation of  the  organic  debris  and  the  concomitant  changes  in  the  sur- 
rounding rock  are  such  as  are  characteristic  of  the  earliest  phase  of  normal 
regional  metamorphism.  The  chemical  reactions  in  the  organic  matter 
are  not  yet  convincingly  explained.  The  processes  are  now  in  opera- 
tion, though  they  are  more  energetic  and  efficient  in  regions  and  during 
periods  of  dias trophic  movement. 

Experimental  evidence  strongly,  but  not  conclusively,  supporting 


10  Observations  by  C.  E.  Van  Orstrand,  of  the  U.  S.  Geol.  Survey,  of  temperatures 
in  several  deep  wells  in  the  Northern  Appalachian  region  indicate  temperatures,  at 
the  present  time,  of  approximately  170°  F.  (77°  C.)  at  depths  of  7500  ft.  (2286  m.), 
the  increase  averaging  1  to  50  ft.  in  depth.     [See  Ohio  Gas  &  Oil  Men's  Jnl  (Sept., 
1919)  1, 22.]     The  temperature  gradient  is  found  to  be  steeper  in  other  regions.     Thus, 
at  a  depth  of  3000  ft.  (914  m.)  at  Newkirk,  Okla.,  it  is  128.1°  F.  (53.5°  C.)  or  1°  F.  per 
46  ft.,  while  in  the  Ranger,  Tex.,  field,  at  3000  ft.  the  temperature  was  134.9°  F. 
(57. 1  °  C. ) ,  the  rate  of  increase  being  1  °  to  45  ft.     No  doubt  very  much  steeper  gradients 
will  be  found  in  regions  of  more  recent  movement. 

11  Studies  of  the  petrology  of  oil  sands  are  now  in  progress  by  M    I.  Goldman,  of 
the  U.  S.  Geol.  Survey. 


DAVID   WHITE  185 

the  pressure  theory  of  the  origin  of  oil  has  recently  been  adduced12  by 
Alex.  W.  McCoy,  geologist  of  the  Empire  Gas  and  Fuel  Co.  By  means 
of  pressure  on  the  ends  of  a  cylinder  of  oil  shale  enclosed  in  a  tube,  the 
walls  of  which  were  thinner  in  the  central  zone  than  at  the  ends,  so  as  to 
allow  bulging,  Mr.  McCoy  was  able  to  induce  flowage  in  the  oil  shale,  and, 
without  causing  an  appreciable  amount  of  heat,  developed  small  globules 
of  oil  in  the  shale  which  were  visible  with  a  hand  lens.  The  material 
used  in  the  experiment  was  typical  oil  shale,  capable  of  yielding  25  gal. 
(94.6 1.)  of  oil  to  the  ton,  and  having  a  crushing  strength  of  about  3000  Ib. 
per  sq.  in.  (211  kg.  per  sq.  cm.).  No  oil  could  be  removed  by  solvents 
prior  to  the  experiment.  From  this  and  other  experiments,  Mr.  McCoy 
concludes:  (1)  that  the  solid  bituminous  material  in  the  rocks  is  only 
changed  to  petroleum  by  pressure  in  local  areas  of  differential  movement ; 

(2)  that  "the  accumulation  of  oil  into  commercial  pools  is  accomplished 
by  capillary  water;    and  this  interchange  only  takes  place  in  local  areas 
where  the  oil-soaked  shale  is  in  direct  contact  with  the  water  of  the  res- 
ervoir rock,"  such  conditions  being  explainable  either  by  joints  or  faults; 

(3)  that  "some  adjustment  takes  place"  until  the  oil  in  the  sand  has 
found  the  larger  openings,  where  it  remains  indefinitely;  (4)  that  "the 
amount  of  oil  in  any  field  could  have  been  derived  from  normal  bitu- 
minous shales  in  close  proximity  to  the  pay  horizon;"  (5)  that  areas  of 
maximum  differential  movement  are  in  accord  with  anticlinal  structures, 
that  the  maximum  sub-surface  faulting  is  on  the  flanks  and  sides  of  the 
anticlines,  and  that  the  best  production  runs  in  trends  parallel  to  the 
faulted  zone.     The  most  important  part  of  Mr.  McCoy's  experiments, 
as  it  seems  to  me,  is  the  production  of  petroleum  by  pressure  alone  acting 
on  unaltered  shale. 

As  noted  in  my  discussions  of  coal,  regional  carbonization  results  from 
the  progressive  devolatilization  of  carbonaceous  matter  in  the  strata 
on  a  regional  scale  under  dynamic  stresses,  dominantly  horizontal  thrusts, 
probably  with  development  of  moderate  temperatures.  It  is  most 
advanced  in  the  regions  of  apparently  greatest  thrust  compressions 
and  hence  of  greatest  molecular  displacement;  and  in  any  region  it 
is  seen  to  be  greatest  on  the  side  of  greatest  cumulative  and  sustained 
horizontal  stresses. 

With  reference  to  both  carbonization  and  folding,  it  is  important  for  a 
field  geologist,  prospecting  for  oil  in  new  regions,  to  remember  that  folds 
are  likely  to  mark  lines  of  pre-existent  weakness  resulting  from  former 
anticlinal  buckling  or  faulting  in  the  deeper  strata,  or  that  they  may  occur 
in  zones  of  less  competence,  such,  for  example,  as  along  zones  of  marked  or 
abrupt  unconformities;  also  that  buckling  and,  in  particular,  overthrusts 
are  the  structural  changes  (really  strains)  that  compensate  and  relieve 

14  Notes  on  Principles  of  Oil  Accumulation:  Jnl  Geol  (1919)  27,  252-262. 


186       GENETIC   PROBLEMS   AFFECTING   SEARCH   FOR   NEW   OIL   REGIONS 

the  pressure  stresses  and  tend  to  neutralize  them  through  a  relatively 
easy  and  quick  shortening  of  the  arc  which  would  otherwise  take  place 
through  compression  only.  The  buckling  may  occur  at  an  early  stage 
of  the  thrust,  giving  comparative  relief  through  the  remainder  of  the 
movement  and  even  through  the  periods  of  greatest  intensity  of  move- 
ment. Accordingly,  a  buttress  of  horizontal  competent  strata  under 
adequate  loading  may  endure,  and  undoubtedly  has  in  many  cases, 
more  vigorous  and  long  continued  differential  stresses,  and  has  sustained 
greater  molecular  displacement  and  compacting  of  the  rock,  incident  to 
actual  compression,  than  a  folded  series,  even  though  the  thrust  may 
actually  have  been  stronger  and  covered  a  greater  distance  in  the  latter 
region.  The  study  of  the  carbonization  in  a  number  of  coal  fields  shows 
this  to  be  true. 

It  appears  probable  that,  in  regions  where  the  thrusts  have  been 
sufficient  to  cause  well  loaded  strata  to  form  anticlines,  the  stresses  have 
been  great  enough  to  cause  the  generation  of  petroleum.  If  these 
deductions  are  well  founded,  the  earlier  and  minor  stresses  are  connected 
with  the  production  of  the  heavier  oils,  anomalous  or  even  inexplicable 
as  this  may  seem  from  the  chemical  standpoint,  while  the  highest  grade 
oils  are  usually  found  where  the  carbonization,  resulting  from  more  intense 
stresses,  has  approached  the  limit  of  oil  production. 

According  to  these  observations,  and  contrary  to  the  views  of  most 
geologists  and  chemists,  it  would  appear  that  the  heavy  oils,  occurring 
in  regions  of  less  thrust  and  alteration,  are  the  first  products  of  oil  genera- 
tion, while  the  light  oils,  occurring  in  the  regions  of  greater  thrust,  are 
the  more  refined  products.  Whether  the  latter  are  to  be  regarded  as  the 
direct  result  of  the  greater  compression  of  organic  matter  or,  perhaps  more 
likely,  as  oils  that  have  undergone  subsequent  migration,  probably  with 
fractionation  by  geologic  processes,  remains  to  be  proved.  In  this 
connection,  it  is  to  be  borne  in  mind  that  the  solid  residues  of  heavy 
hydrocarbons,  devolatilized  in  the  shales  and  other  strata  during  the 
destructive  stages  beyond  the  oil  limits,  are  now  in  evidence  as  particles 
of  carbon,  causing  the  blackness  of  slates,  some  of  which  were  once 
richly  carbonaceous  shales,  and  undoubtedly  productive  deposits  of  oil 
mother  substance. 

On  the  other  hand,  it  would  appear  probable  that,  in  general,  oil 
either  is  not  present  or  is  not  segregated  in  series  of  sedimentary  forma- 
tions that  have  never  been  thrust  sufficiently  to  cause  some  buckling  or 
undulation  under  favorable  conditions,  with  the  requisite  amount  of 
loading.  If  not  sufficiently  loaded,  they  are  likely  to  remain  unconsoli- 
dated  though  they  may  have  been  folded.  In  the  Coastal  Plain  forma- 
tions of  the  Atlantic  States,  which  appear  to  be  but  slightly  warped  and 
possibly  lack  good  anticlines  and  domes,  as  though  the  region  had  been 
lifted  bodily,  without  local  disturbance,  on  the  back  of  the  metamorphic 


DAVID   WHITE  187 

basement  complex,  the  apparent  absence  of  oil  pools  is  attributed  by  some 
geologists  to  the  lack  of  folds;  this  explanation  is  more  likely  to  be  correct 
than  the  view  that  it  is  due  to  the  absence  of  sufficient  organic  matter 
in  the  formations.  But  it  is  also  probable  that,  over  much  of  the  area, 
the  unaltered  sedimentary  strata  have  not  been  thick  enough  to  assure 
the  requisite  loading  had  moderate  folding  taken  place. 

In  the  genesis  of  an  oil  pool  not  only  is  the  organic  debris  altered  and 
devolatilized,  with  the  generation  of  petroleum  and  natural  gases,  as  the 
result  of  dynamic  thrust  stresses  attending  diastrophic  movements,  but 
the  migration  and  segregation  of  these  hydrocarbons,  disseminated  in 
their  place  of  origin  in  the  mother  rock,  are  promoted,  if  not  caused,  by 
the  molecular  rearrangement  and  the  movement  of  rock  grains  consequent 
to  these  stresses.  Most,  by  far,  of  the  oil  and  gas  is  generated  under  the 
influence  of  differential  stresses  in  " impervious"  beds,  the  larger  part 
being  formed  in  the  midst  of  typically  impervious  deposits,  mainly  organic 
muds,  carbonaceous  clays,  fine-grained  shales,  and  dense  organic  strata, 
such  as  oil  shales,  than  which  few  unaltered  sediments  can  be  more  im- 
pervious. The  molecular  displacement  and  the  readjustments  of  the 
particles  of  the  rock  are  essential  to  the  migration  of  the  newly  formed  oil 
and  gas,  and  of  the  water,  in  the  directions  of  least  resistance,  which, 
other  things  being  equal,  will  be  toward  those  beds,  or  regions  of  beds,  most 
resistant  to  pressure  and  within  the  pore  spaces  of  which  the  pressure  will 
be  relatively  less.  Sandy  strata,  sandstones  with  grains  varying  in  size 
and  shape,  porous  limestones;  lavas,  and,  finally,  coarse  sandstones  com- 
posed of  round  grains  of  uniform  size,  display  varying  resistances  to 
compression,  with  corresponding  variation  of  pore-space  pressure.  Coa- 
lescence of  the  infinitesimal  globules  of  oil  will  take  place  enroute  from  the 
yielding  to  the  resistant  strata;  and  as  the  porous  resistant  beds  with 
stable  grains  are  traversed,  concentration  and  segregation  of  the  oil,  gas, 
and  water  will  ensue,  the  water  driving  the  oil  and  gas  into  the  larger 
voids  by  reason  of  its  greater  capillary  tension,  whereby  it  tends  to  seize 
and  hold  the  smaller  ones. 

The  extent  to  which  argillaceous  and  organic  sediments  are  reduced  in 
volume  under  pressure  is  better  realized  when  one  recalls  that  the  sub- 
surface layer  of  a  peat  bog  contains  from  80  to  90  per  cent,  of  water,  and 
sub-surface  slimes  and  muds  carry  nearly  as  much.  At  the  lignitic 
(brown  coal)  stage,  the  average  water  contents  of  the  coal  bed  approaches 
38  per  cent.;  the  proportions  of  water  in  sub-bituminous,  low-rank 
bituminous,  high-rank  bituminous,  and  semi-bituminous  coals  average 
23,  15,  6,  and  3  per  cent,  respectively.13  To  the  water  losses,  a  part 
of  which  may  be  attributed  to  mere  loading  soon  after  deposition, 
are  to  be  added  the  progressive  losses  of  organic  volatile  matter,  including 

"  G.  H.  Ashley:  Trans.  (1920)  63,  782. 


188       GENETIC   PROBLEMS   AFFECTING   SEARCH   FOR   NEW   OIL   REGIONS 

petroleum.  The  necessity  for  readjustments  of  the  rock  material,  as  the 
process  goes  forward  under  heavy  loading  and  powerful  lateral  thrusts,  is 
obvious.14  Rearrangement  of  the  grains  in  an  impure  sandstone,  or  in  one 
composed  of  grains  varying  in  size  and  irregular  in  shape,  will  permit  less 
compression  than  purer  coarse  sandstone;  while  a  coarse,  porous  sandstone 
composed  of  round  grains,  if  not  too  rigidly  cemented,  may  even  change 
its  shape  under  lateral  thrust  without  change  of  volume,  until  the  stresses 
become  so  great  as  to  deform  the  grains,  at  which  stage  carbonization 
will  have  passed  the  oil  limit.  All  these  conditions  tend  to  drive  the  oil 
into  the  sand  having  the  largest,  roundest,  and  most  uniform  sized  grains. 

It  may  not  be  out  of  place  here  to  note  that  diastrophic  movement  is 
not  simple  or  cataclysmic.  It  is  always  in  progress  in  one  region  or 
another,  though  its  magnitude  and  vigor  are  specially  noticeable  in  periods 
of  most  marked  isostatic  adjustment.  These  periods,  though  for  the 
most  part  relatively  short,  geologically  speaking,  doubtless  span  thou- 
sands or  perhaps  hundreds  of  thousands  of  years.  The  complex  movement 
of  a  lateral  thrust  may  be  considered  as  the  product  of  a  cycle,  or  perhaps 
a  series  of  cycles  of  complex  differential  stresses,  possibly  cumulative  for  a 
period,  then  decreasing  in  force,  probably  to  be  renewed  again  and  again 
in  greater  power,  until  compression,  buckling,  or  displacement  have  so 
far  relieved  the  stresses  that  they  are  no  longer  able  to  overcome  the 
rigidity  and  friction  of  the  strata.  There  is  an  obvious  contrast  between 
those  strata  which  relieve  the  intensity  and  continuity  of  a  thrust  by 
buckling,  folding,  or  faulting,  and  those  more  competent  strata  which, 
though  enduring  even  more  intense  stresses,  are  able  to  relieve  them  only 
by  horizontal  compression. 

Plainly,  then,  during  these  periods  of  horizontal  diastrophic  stresses, 
the  opportunities  for  progressive  readjustment  of  the  particles  may  have 
been  almost  without  number.  It  is  reasonable  to  conclude  also  that  mo- 
lecular rearrangements  have  attended  these  stresses,  since  the  chemical 
composition  of  the  organic  debris  and  residues  has  from  time  to  time  cer- 
tainly been  altered,  with  the  generation  and  expulsion  of  volatile  matter,  in- 
cluding oil.  A  study  of  coajs  shows  an  apparently  uninterrupted  gradation 
from  lignite  to  anthracite  and  graphite.  It  would  appear,  therefore, 
that  during  a  period  of  diastrophic  stresses,  the  conditions  have  repeat- 
edly been  favorable  for  the  evolution  of  the  oil,  the  displacement  and 
rearrangement  of  the  organic  particles  and  rock  grains,  the  coincident 

14  Lateral  transfer  or  flowage,  under  differential  pressures,  of  the  more  plastic 
argillaceous  and  organic  strata  in  a  series  of  beds  varying  in  composition  and  thick- 
ness is  most  natural,  and  is  illustrated  by  the  "horses,"  " squeezes,"  "ve:ning,"and 
"pocketing"  of  coal  and  clays,  so  familiar  to  the  miner  in  the  bituminous,  semi- 
bituminous  and  anthracite  fields.  Such  local  flowage  may  cause  thin  included  sand- 
stones or  even  environing  shales  to  bend  in  accommodation,  thus  producing  small 
local  anticlines,  some  of  which  may  be  misinterpreted  as  depositional. 


DAVID   WHITE  189 

rupture,  enlargement,  decrease  or  rearrangement  of  the  pore  spaces  and 
capillaries,  the  development  of  zones  of  varying  pressure,  the  overcoming 
of  friction,  and  the  disorganization  of  capillary  resistance.  In  short,  the 
conditions  must  have  been  most  favorable  (a)  for  squeezing  oil,  gas, 
and  water  out  of  their  impervious  source,  through  the  intervening,  im- 
permeable, organic  and  argillaceous  deposits,  into  the  less  compressed 
regions  of  the  sandy  rocks,  sandstones,  and  porous  limestones;  (6)  for 
their  migration  in  spite  of  capillary  resistance;  and  (c)  for  their  eventual 
escape  into  the  most  porous,  coarse-grained  reservoir  available,  where, 
under  a  relative  stability  of  the  rock  material,  segregation  and  gravita- 
tion may  be  assumed  to  have  taken  place,  subject  to  the  effect  of  capil- 
lary tension.  In  some  respects,  the  effects  of  diastrophic  stresses  in 
compressible  sedimentary  strata  may  be  likened  to  a  jigging  of  rock 
particles  and  mineral  grains,  in  which  process  existing  capillaries  may 
become  unstable  and  disrupted,  pore  spaces  reorganized  as  to  number, 
form  and  size,  and  friction  repeatedly  overcome;  thus  the  escape,  migra- 
tion, concentration,  and  segregation  of  water,  oil  and  gas,  into  less 
compressible  sandstone  and  limestone  reservoirs  were  promoted. 
Consistent  with  this  interpretation,  it  would  appear  that: 

1.  Oil  will  be  generated  only  at  depths  sufficient  to  assure  the  neces- 
sary loading,  which  may  vary  somewhat  with  the  composition  and 
rigidity  of  the  strata  and,  to  some  extent,  with  the  intensity  of  the 
thrust. 

2.  In  oil  fields  where  the  stress  has  been  slight  and  probably  confined 
to  a  single  period,  carbonization  (alteration)  being  in  the  early  stage,  the 
oil  is  not  likely  to  be  found  far,  stratigraphically,  from  the  carbonaceous 
sediments.     If  the  thrusts  have  not  been  sufficient  to  drive  the  water,  oil, 
and  gas  to  a  suitable  storage  "sand,"  the  disseminated  oil  may  not  be 
recoverable.     Water,  with  its  stronger  capillary  tension,  will  tend  to 
drive  the  oil  into  the  largest  pores  available.     Accordingly,  a  lenticular 
body  of  open-pored  coarse  sand  may  be  filled  with  oil  under  heavy  pres- 
sure, independently  of  anticlinal  structure,  or  even  in  a  shallow  struc- 
tural depression. 

3.  The  largest  oil  pools  normally  occur  where  ample  suitable  storage 
is  convenient  to  abundant  organic  mud  or  mother  substance,  unless  the 
thrusts  have  been  too  great  and  carbonization  has  gone  too  far.     Insuffi- 
cient storage  in  very  thin  or  fine-grained  sands  may  be  found  in  extensive 
carbonaceous  formations;  for  example,  the  thin  sands  of  the  Graneros 
in  the  Thornton  field,  Wyoming,  and  the  fine-grained  sands  in  the  Mancos 
shale  in  northwestern  Colorado  and  in  the  Chattanooga  shale  in  Barren 
County,  Ky. 

4.  The  stresses  of  a  diastrophic  movement  may  be  sufficient  to  gene- 
rate only  a  part  of  the  oil  and  gas  derivable  from  the  organic  mother  sub- 
stance, leaving  some  to  be  evolved  under  later  stresses,  until  oil  is  no 


190       GENETIC   PROBLEMS   AFFECTING   SEARCH   FOR   NEW   OIL   REGIONS 

longer  produced,  though  gases  may  continue  to  be  eliminated  until  the 
organic  substance  is  wholly  devolafcilized,  leaving  only  the  "fixed  car- 
bon."15 From  field  observations  on  the  progress  of  devolatilization  of 
organic  matter,  it  is  concluded,  as  already  noted,  that  the  first  oils  are 
generally  heavy,  usually  with  considerable  asphalt;  the  later  products, 
generated  in  areas  of  more  advanced  alteration,  are  lighter;  while  the  oils 
from  formations  and  regions  where  the  carbonization  limit  has  been 
approached  are  characteristically  of  the  highest  grade.  This  is  the 
reverse  of  the  order  in  which  fractions  are  obtained  by  heat  distillation. 

5.  In  the  course  of  successive  periods  of  lateral  diastrophic  stresses, 
the  water,  oil,  and  gas,  under  cumulative  pressures,  may  be  carried  through 
relatively  impervious  rocks  for  long  distances  in  the  direction  of  least 
resistance,  if  the  thrusts  and  consequent  pressures  are  sufficiently  ener- 
getic, capillary  tension  and  friction  being  to  some  extent  counteracted 
by  the  forces  which  cause  rearrangement  of  the  rock  particles.     For  this 
reason,  several  sands  may  yield  oil  generated  from   a  single  deposit. 
Enormous  pressures  should  develop  in  the  lower  sands.     In  fields  con- 
taining many  oil  sands,  the  oil  is  more  likely  to  be  of  deep  origin. 

6.  Oil  pools  generated  and  localized  during  one  period  of  stress  may  be, 
and  probably  have  been,  carried  on  to  new  reservoirs,  possibly  at  differ- 
ent horizons,  at  a  later  period  of  greater  stress.     This  may  be  termed 
secondary  migration  and  secondary  storage.     It  seems  within  the  limit 
of  probability  that  some  of  the  oil  found  in  sands  stratigraphically 
remote  from  recognizably  carbonaceous  beds  may  have  come  from  the 
latter  by  secondary  if   not  by  primary  migration.     Given  sufficient 
stresses  in  a  great  thickness  of  compressible  strata,  or  pressures  sufficient 
to  compress  the  interlaminated  somewhat  arenaceous  beds,  it  would  seem 
possible  that  some  of  the  water,  oil,  and  gas  may  be  forced  comparatively 
near  the  surface  before  they  are  trapped  in  a  sandstone  beneath  im- 
pervious cap-rock;  finally,  if  these  sandstones  lie  sufficiently  near  the 
surface  to  crack,  fracture,  or  buckle  under  thrust  displacement,  the  oil 
and  gas  may  even  escape  from  the  strata.     Consideration  must  be  given 
to  the  probable  depth  of  erosion  that  has  occurred  in  a  field,  where 
sands  now  near  the  surface  are  productive. 

Whether  there  is  a  sort  of  natural  fractionation  when  the  oil  pool,  at 
a  later  period  of  stresses,  is  forced  into  new  and  perhaps  stratigraphically 
higher  reservoirs,  cannot  now  be  answered  definitely.  The  facts  that 
(a)  the  oil  disappears  eventually  in  a  process  of  advanced  carbonization, 
leaving  only  its  solid  residues  as  dark  carbonaceous  matter  in  the  rocks, 


16  This  is  indicated  by  the  artificial  distillation  of  oil  from  oil  shales  in  regions 
which  have  undergone  varying  degrees  of  carbonization,  up  to  the  oil  limit;  only  small 
amounts  of  oil  can  be  obtained  from  shales  which  have  been  carbonized  beyond  this 
limit. 


DAVID    WHITE  191 

and  that  (6)  a  thin  film  of  oil,  including  some  of  the  heavier  hydrocarbons, 
is  left  on  the  grains  around  which  oil  has  stood,  point  toward  the  improve- 
ment of  the  product  with  each  such  transfer.  This  might  account  for 
the  progressive  refinement  of  the  oils  in  the  course  of  recurrent  periods 
of  thrusting,  as  mentioned  under  paragraph  4.  The  possible  depreciation 
of  the  oil  by  percolating  surface  waters,  especially  those  carrying  sul- 
fates,  or  by  escape  of  the  lighter  matter  to  the  surface,  must  not  be 
overlooked. 

The  problems  of  secondary  migration  of  oil  may  be  as  important 
as  they  are  interesting,  and  require  further  study  in  both  field  and 
laboratory. 

The  disappearance  of  oil  pools  in  areas  of  too  advanced  carbonization 
may  be  due  to  leakage  when  jointing  and  cleavage  become  more  highly 
developed;  or  the  oil  may  have  been  driven  to  the  surface  up  the  dip  of 
the  sands;  or,  as  I  am  inclined  to  believe,  it  may  have  been  volatilized, 
the  solid  residues  remaining  in  the  rock. 

Whether  it  is  possible  for  oil  and  gas  to  pass  through  impermeable 
clay  shales  or  other  cap-rocks  except  at  times  of  diastrophic  readjust- 
ment may  well  be  doubted.  The  extent  to  which  such  readjustments 
are  essential  to  the  migration  of  oil,  gas,  and  water  along  a  stratum  so 
composed,  as  to  size  of  grains  and  porosity ,  as  to  comprise  an  oil  sand, 
remains  to  be  experimentally  proved;  but  I  am  disposed  to  believe  that 
their  migration  through  " tight "  sands  and  other  so-called  impervious 
beds  takes  place  under  dynamic  stresses  of  diastrophism. 

C.  E.  Van  Orstrand  suggests  that  the  geologists  of  the  country  may 
not  have  given  due  consideration  to  the  possible  influence  of  osmotic 
pressure  in  moving  the  oil  from  deeper  and  warmer  strata,  in  which  it 
originates,  to  the  overlying  cooler  strata  or  up  the  dip  into  the  zones  of 
lower  temperature  at  the  apex  of  an  anticline  or  dome.  This  subject 
has  been  mentioned  by  Mr.  Van  Orstrand  in  the  record  of  his  temperature 
observations  in  several  deep  wells  of  West  Virginia  and  southwestern 
Pennsylvania.16  In  this  connection,  attention  is  called  to  a  brief 
discussion,  by  H.  B.  Gillette,17  of  the  influence  of  osmotic  pressure  in 
transferring  rock  solutions  from  warmer  to  cooler  zones,  as  relating  to 
the  deposition  of  orebodies. 

The  oil  in  the  salt  domes  of  the  Gulf  Coastal  Plain  may  have  originated 
in  the  strata  in  which  the  salt  plug  is  found,  or  it  may  have  ascended 
more  or  less  of  the  distance  traversed  by  the  salt.  The  pressure  theory 
as  to  the  origin  of  the  salt  plugs,  which  seems  to  demand  acceptance, 


16  Discussion  of  the  records  of  some  very  deep  wells  in  the  Appalachian  oil  fields 
of  Pennsylvania  and  West  Virginia,  by  I.  C.  White,  State  Geologist,  with  temperature 
measurements  by  C.  E.  Van  Orstrand. 

«  Trans.  (1903)  34,  710. 


192       GENETIC   PROBLEMS   AFFECTING   SEARCH   FOR   NEW   OIL   REGIONS 

premises  local  pressures  in  the  surrounding  rocks  which  might  be  sufficient 
to  cause  the  generation  of  such  low-grade  oils  as  are  usually  found  in 
these  domes.  Oil  of  higher  grade  would  be  expected,  in  general,  at 
great  depth.  On  the  other  hand,  it  has  not  been  proved  that  the  oil  did 
not  ascend  with  the  salt,  which  seems  possible.  In  the  latter  case  the 
domes  may  deserve  testing  to  a  maximum  depth.  Proof  that  the  oil 
was  disseminated  in  the  strata,  in  readiness  to  migrate  horizontally  into 
the  monoclines  about  a  dome  when  the  latter  was  formed,  would  support 
the  theory  that  the  oil  was  biochemically  formed  at  the  time  of  deposi- 
tion of  the  strata,  as  suggested  by  Murray  Stuart,18  separated  by 
pressure,  and  segregated  gravitationally  in  the  upturned  beds 
surrounding  the  plug. 

THICKNESS  OF  SEDIMENTARY  FORMATIONS 

Whether  or  not  the  geologist  follows  my  conclusion  as  to  carboniza- 
tion, and  its  use  as  an  index  of  incipient  regional  alteration,  the  degree  of 
which  approximately  determines  the  limit  beyond  which  productive  oil 
fields  will  not  be  found,  he  must  in  any  case  take  into  account  not  only  the 
alteration  of  the  sedimentary  formations,  according  to  his  own  concep- 
tion of  the  metamorphic  limits,  but  also  the  thickness  of  sediments  that, 
according  to  his  judgment,  are  not  too  altered,  and  hence  must  furnish 
the  oil.  However,  this  subject  has  awakened  less  discussion,  and  there- 
fore less  systematic  observation,  than  its  very  great  importance  demands. 

It  will  probably  be  generally  agreed  that  the  requisite  thickness  of 
sedimentary  strata  in  any  oil  basin  depends  on  the  character,  composi- 
tion, and  competence  of  the  strata;  the  position  of  the  sands  and  the  cap- 
rock;  the  distribution  of  the  mother  substance;  the  structure,  the  jointing, 
faulting,  erosion,  conditions  of  deposition,  etc.  Mother  substance,  reser- 
voir sands,  or  cap-rock  may,  of  course,  be  lacking,  but  for  purposes  of 
discussion,  it  must  be  assumed  that  they  are  all  present  and  favorable, 
i.e.,  the  organic  matter  is  near  but  not  at  the  bottom,  and  the  reservoir 
and  cap-rock  are  next  above  it.  Further,  a  consideration  of  the  requisite 
thickness  must  take  into  account  the  probable  depth  of  strata  eroded  since 
the  oil  was  generated  and  brought  to  its  present  storage.  In  other  words, 
the  original  thickness  at  the  time  of  deformation  by  horizontal  stresses 
is  to  be  regarded,  rather  than  the  present  thickness  in  the  producing 
basins,  for  the  original  thickness  is  what  determined  the  amount  of  load 
on  the  organic  beds  when  dynamic  action  occurred. 

A  review  of  the  field  evidence  circumstantially  presented  by  oil  fields 
possessing  relatively  thin  and  not  too  altered  strata,  lying  on  a  crystal- 
line or  thoroughly  metamorphosed  basement  complex,  would  be  both 

18  Records  Geol.  Survey  India  (1910)  40,  320-333. 


DAVID    WHITE  193 

interesting  and  valuable,  but  the  data  seem  insufficient  for  definite  con- 
clusions. I  do  not  recall  any  oil  field,  meeting  the  conditions  above  men- 
tioned, in  which  the  non-metamorphosed  sediments  originally  aggregated 
less,  in  round  numbers,  than  2000  ft.  (600  m.) ;  in  most  cases  the  thickness 
is  over  2500  ft.  (760  m.).  '  Exceptions  should  be  made  of  series  marginally 
overlapping  on  metamorphics,  like  the  Pennsylvanian  and  Permian  on 
the  buried  igneous  and  metamorphic  rocks  in  portions  of  the  Mid-Conti- 
nent region,  where  the  hydrocarbons  may  have  migrated  diagonally 
through  the  littoral  sands  of  the  relatively  steeply  transgressive 
formations. 

The  question  of  thickness  is  possibly  of  great  importance  in  regions 
like  the  Atlantic  Coastal  Plain,  where  unaltered  and  largely  unconsoli- 
dated  sediments  lie  on  pre-Cambrian  complexes;  also  in  portions  of  the 
Atlantic  Trias.  As  to  the  Atlantic  Coastal  Plain,  over  the  greater  por- 
tion of  which  the  thickness  of  the  Coastal  Plain  deposits  is  almost  cer- 
tainly less  than  2200  ft.  (670  m.),  while  throughout  large  areas  it  is  less 
than  1200  ft.  (366  m.),  it  may  be  questioned  whether,  if  thrusts  sufficient 
for  the  generation  and  migration  of  oil  into  coincidentally  induced  folds 
had  been  exerted,  the  sediments  were  sufficiently  thick  to  provide 
enough  loading  to  favor  the  generation,  segregation,  and  retention  of 
the  oil  and  gas.  Almost  surely  the  thickness  has  been  too  little,  also, 
over  considerable  areas  in  those  marginal  zones  of  the  Coastal  Plain 
formations  in  the  Gulf  embayment,  where  the  Cretaceous  and  Tertiary 
sediments  lie  on  metamorphic  or  crystalline  series. 

On  the  other  hand,  the  presence  of  oil  in  relatively  thin  sediments 
overlying  other  sedimentary  formations,  in  which  the  carbonization  has 
not  gone  far  beyond  the  limit  cited  above,  may  not  be  precluded,  in 
accordance  with  the  suggested  migration  of  hydrocarbons  during  recur- 
rent periods  of  thrust  stresses.  The  Madill,  Okla.,  field  seems  to  offer 
an  illustration.  The  stresses  inducing  incipient  metamorphism  in  an 
unconformably  overlying  formation  must  further  alter  the  lower  forma- 
tion, which  may  already  have  nearly  reached  the  carbonization  limit. 
However,  the  presence  of  oil  pools  in  thin  unaltered  sediments,  where  the 
alteration  of  the  carbonaceous  debris  in  underlying  formations  has 
progressed  considerably  past  the  carbonization  limit — say,  into  the 
semi-bituminous  (fuel  ratio  3.0  or  more)  or  the  semi-anthracite  rank — 
would  be  very  interesting  and  worthy  of  record.  In  such  an  occur- 
rence, the  questions  will  be:  Did  the  oil  (a)  originate  in  the  lower  series 
and  pass  into  the  younger  by  primary  or  secondary  migration,  as  seems 
most  probable;  (6)  condense  from  vapors  generated  in  the  lower  series 
during  the  progressive  alteration  after  the  upper  sediments  were  laid 
down;  or  (c)  originate  in  the  upper  series? 

The  evidence  bearing  on  these  questions  is  not  sufficiently  complete 
and  coordinated  to  encourage  a  satisfactory  discussion  at  this  time,  due 

VOL.   UCV. 13. 


194   GENETIC  PROBLEMS  AFFECTING  SEARCH  FOR  NEW  OIL  REGIONS 

largely  to  the  lack  of  observation  on  carbonization  and  other  indices  of 
incipient  metamorphism  of  the  sediments,  including  the  carbonaceous 
deposits.  Factors  to  be  considered  in  this  connection  include  uncon- 
formities at  erosional  intervals,  as  affecting  the  escape  or  deterioration 
of  oils  near  the  old  erosion  surfaces;  migration  of  oil  and  gas  up  the  dips 
to  the  margins  of  transgressing  formations  or  through  littoral  zones  to 
higher  formations;  thicknesses  of  rock  eroded  from  producing  formations; 
and  the  effects  of  sealing  on  oil  pools  in  the  sands.  The  application  of 
the  problem  to  many  regions  is  obvious. 

CONDITIONS  OF  DEPOSITION 

Aside  from  such  facts  as  the  presence  of  adequate  organic  matter, 
of  sands  suitably  composed  and  situated  for  service  as  oil  reservoirs,  of 
cap-rocks  properly  located,  etc.,  some  of  which  have  already  been  men- 
tioned, a  question  which  should  not  be  ignored  in  the  search  for  oil 
in  a  new  region,  such,  for  example,  as  the  Tertiary  freshwater  basins  of 
eastern  Washington  and  Oregon,  or  in  the  Great  Basin  region,  is  whether 
or  not  the  beds  concerned  in  the  generation  and  storage  of  the  oil  are 
strictly  of  freshwater  origin,  and  particularly  whether  the  oil-bearing 
series  was  laid  down  in  an  exclusively  non-marine  basin.  Inseparably 
connected  with  this  question  is  the  related  one  as  to  the  importance  of  the 
association  of  salt  water  or  gypsum  in  the  oil-producing  formations,  as  is 
so  insistently  urged  by  some  geologists,  with  citation  of  circumstantial 
evidence.  On  these  matters  opinion  differs  widely,  possibly  without 
succinct  data  sufficient  for  a  final  decision. 

As  criteria  to  be  considered  in  the  answering  of  this  problem  the 
following  may  be  noted: 

(1)  Ample  organic  matter  undoubtedly  suitable  for  the  generation 
of  oil  and  gas  was  deposited  with  the  sediments  in  many  of  the  fresh- 
water basins.     These  deposits  contain  oil  shale  of  high  quality,  which, 
on  distillation,  yields  oil  essentially  like  and  possibly  indistinguishable 
from  that  obtained  from  oil  shales  of  marine  origin.     Many  of  the  organic 
products  are  common  to  both  habitats. 

(2)  The  mechanical  constitution  of  the  deposit  in  both  marine  and 
freshwater  formations  is  essentially  the  same. 

(3)  Important  oil-bearing  sands  and  organic  remains  were  deposited 
during  intervals,  sometimes  of  considerable  length,  during  which  only 
freshwater  sediments  were  laid  down,  these  deposits  being  intercalated 
in  brackish  water  or  marine  sediments. 

(4)  Oil-bearing  sands  and  organic  deposits  were  laid  down  in  waters, 
but  slightly  saline,  in  the  younger  formations  of  the  Appalachian  trough. 

(5)  Some  salts  are  present  in  freshwater  deposits. 

(6)  Natural  gas  is  present  in  freshwater  basins,  and  has  been  devel- 
oped at  considerable  depth  in  such  basins. 


DISCUSSION  195 

(7)  While  it  may  be  true  that,  in  the  geologic  processes  of  oil  genera- 
tion, salt  in  amounts  premising  marine  or  brackish  water  deposition  may 
be  essential  as  a  catalyzer  or  otherwise,  the  fact  remains  to  be  demon- 
strated, possibly  in  the  laboratory.  The  absence  of  salt  does  not  appear 
to  affect  the  artificial  production  of  oil  by  distillation  of  shale. 

It  is  possible  that  in  some  of  our  oil  fields,  salt  water  may  have  found 
its  way  downward  through  joints  or  along  the  dip  into  fresh- water  beds 
subsequently  submerged  beneath  the  sea,  somewhat  like  the  invasion 
of  fresh  water  down  the  dips  of  some  of  the  marine  oil  sands  in  California. 
On  the  other  hand,  fresh- water  basins  in  which  the  requisite  conditions 
as  to  depth,  organic  matter,  sands,  cap-rocks,  thrusting,  and  incipient 
alteration  favorable  for  oil  pools  are  fulfilled,  and  which  have  never  sub- 
sequently been  submerged  beneath  the  sea,  have  been  too  little  tested 
to  justify  conclusions  as  to  their  possibilities  for  oil  production.  Such 
basins,  if  actually  closed  and  without  outlet,  will  be  more  or  less  dis- 
tinctly alkaline.  At  the  present  stage  of  our  knowledge,  fresh-water 
basins  appearing  otherwise  to  meet  the  requirements  should  be  wildcatted 
without  prejudice. 

DISCUSSION 

X 

R.  H.  JOHNSON,  Pittsburgh,  Pa. — It  seems  to  me  that  the  case  for 
the  fresh-water  origin  of  natural  gas  must  be  accepted,  since  the  coal 
progressively  loses  methane.  We  know  that  much  natural  gas  must 
have  arisen  in  that  way.  My  reserve  in  connection  with  petroleum  in 
contrast  with  natural  gas  comes  from  the  fact  that  if  the  fresh-water 
deposits  have  been  as  productive  of  petroleum  as  the  marine,  the  field 
evidence  ought  to  show  us  more  petroleum  in  close  proximity  to  the  coal; 
it  is  this  that  leaves  me  skeptical  as  to  very  much  fresh-water  petroleum, 
although  we  must  admit  a  great  deal  of  fresh- water  natural  gas. 

H.  W.  HIXON,  New  York,  N.  Y. — In  the  Appalachian  field,  how 
much  oil  and  gas  do  you  find  above  the  coal?  I  am  not  well  informed 
on  that  subject,  but  I  have  not  heard  of  a  case  where  oil  and  gas  occurred 
above  the  coal  in  Pennsylvania  or  West  Virginia,  except  possibly  that 
which  had  migrated  there  along  a  fault.  There  is  another  thing,  you 
cannot  saponify  petroleum  and  you  cannot  make  glycerine  out  of  petro- 
leum. If  you  could  do  that,  why  should  we  have  paid  such  high  prices 
for  glycerine  during  the  war?  You  can  saponify  organic  oil  and  you  can 
make  glycerine  out  of  animal  fats,  so  that  the  petroleum  and  animal 
fats  differ  entirely.  Also,  petroleum  has  no  food  value. 

We  differ  fundamentally  as  to  our  ideas  about  the  origin  of  petro- 
leum and  natural  gas,  and  I  think  we  will  have  to  let  it  go  at  that.  As 
regards  the  origin  of  the  force,  the  dynamic  force,  that  causes  these 
deformations,  the  elevation  and  folding,  I  consider  that  these  gentlemen 


196       GENETIC   PROBLEMS   AFFECTING   SEARCH   FOR   NEW   OIL   REGIONS 

are  laboring  under  the  impression  that  it  is  contraction.  I  have  studied 
that  question  for  a  number  of  years  and  find  that  the  best  authorities  on 
the  subject  state  that  the  total  amount  of  contraction  of  the  interior  of 
the  earth,  due  to  loss  of  temperature,  in  100,000,000  years  would  prove 
a  circumferential  contraction  of  about  7  miles,  and  that  if  all  of  the  folding 
and  faulting  and  overthrust  of  the  various  mountain  ranges  of  the  earth 
were  ironed  out,  they  would  amount  to  something  like  150  to  200  miles. 
There  is  a  decided  difference  that  has  to  be  accounted  for.  I  account  for 
it  in  an  entirely  different  way;  that  the  gases  which  cause  elevation  by 
reduction  of  density,  as  the  surface  of  a  loaf  of  bread  is  raised  by  reduction 
of  density,  tend  to  accumulate  and  migrate  toward  the  axis  of  elevation. 
They  carry  the  crust  in  two  directions  and,  because  of  the  reduced  den- 
sity, creep  toward  the  axis  of  elevation  or  toward  the  center  of  the 
dome.  The  hydrocarbons  are  in  the  gaseous  interior  of  the  earth  for 
exactly  the  same  reasons  as  all  the  other  gases — because  of  the  diffusion 
of  gases  in  the  original  gaseous  planet  in  that  gaseous  core,  and  they  have 
remained  there  ever  since,  being  held  by  the  power  of  diffusion.  The 
change  from  the  gaseous  to  the  solid  condition  is  by  loss  of  temperature. 
It  then  becomes  lighter  at  the  same  time,  because  the  gaseous  core  must 
be  denser  than  the  solids  that  lie  upon  it. 

My  contention  is  that  petroleum,  natural  gas,  and  the  helium  with 
them  are  of  volcanic  origin.  The  origin  of  oil  and  gas  is  connected  with  the 
whole  theory  of  earth  physics,  which  is  entirely  different  from  the  old 
contraction  hypothesis,  on  which  most  of  the  geologists  base  their  theory 
of  mountain  formation. 

The  authorities  on  the  subject  state  that  the  earth's  crust,  considered 
as  a  dome,  is  not  capable  of  supporting  one  five-hundredth  part  of  its 
own  weight.  If  it  is  not  capable  of  supporting  any  more  than  that  por- 
tion of  its  own  weight,  it  must  be  supported  by  the  material  below  it  at 
all  time?,  whether  it  is  above  sea  level  or  below  sea  level.  We  find  rocks 
of  marine  origin  in  the  highest  mountains.  They  did  not  get  there  by 
accident;  and  if  they  were  supported  by  the  material  below  them  at  all 
times,  and  they  are  above  sea  level  at  one  time  and  below  sea  level  at  a 
previous  time,  the  only  possible  solution  of  that  problem  is  that  the 
matter  below  the  zone  of  fracture  has  varied  in  density  between  those 
two  periods.  So  that  you  come  to  a  question  of  accounting  for  that 
variation  in  density  between  two  geological  periods;  that,  I  maintain, 
is  due  to  the  accumulation  of  magmatic  gases  derived  from  the  gaseous 
core  denser  than  the  solids  which  will  form  out  of  it  when  cold. 

DAVID  REGER,*  Morgantown,  W.  Va. — Regarding  the  statement  just 
made  that  oil  has  not  been  found  above  the  coals  in  the  Appalachian 
Basin,  I  would  like  to  say  that  one  of  the  first  wells  in  the  West  Virginia 

*  Assistant  Geologist,  West  Virginia  Geol.  Survey. 


DISCUSSION  197 

fields  was  about  300  ft.  deep,  at  Burning  Springs  on  the  Little  Kanawha 
River  in  1860.  When  I  visited  the  well  in  1909,  49  years  after  its  com- 
pletion, it  was  still  producing  30  bbl.  of  oil  a  month  and  10  years  later, 
in  1919,  was  still  producing.  Only  the  owner  knows  how  many  thousands 
of  barrels  the  well  has  actually  produced  in  that  time.  The  producing 
formation  there  was  the  Cow  Run  sand,  which  is  right  in  the  middle  of 
the  Coal  Measures.  This  well  is  on  the  Burning  Springs  which  extends 
half  way  across  the  state.  The  great  producing  sands  have  been  the 
two  Cow  Runs,  which  have  coal  measures  above  and  below  them.  It 
is  my  opinion  that  while  the  first  oil  in  the  state  was  found  in  the  coal 
measures,  it  is  entirely  possible  that  the  last  drilling  and  the  last  produc- 
tion of  oil  to  be  eventually  found  in  the  state  will  be  in  the  same  coal 
measures. 

H.  W.  HEXON. — I  believe  I  stated  that  if  the  oil  or  gas  migrated  to 
that  particular  place  along  a  fault  it  might  be  found  there,  but  it  all  comes 
from  below  the  coal. 

DAVID  REGEB. — There  is  no  fault  there. 

J.  F.  DUCE,  Denver,  Colo,  (written  discussion). — The  question 
of  the  presence  of  carbonaceous  material  in  the  "Red  Beds,"  is  an  old 
one.  The  Triassic  "  Red  Beds  "  of  New  Mexico  are  certainly  carbonaceous 
and  at  times  bituminous.  Certain  of  the  sandstones  are  crowded  with 
fossil  wood,  while  directly  above  these  wi^  be  found  bituminous  sands. 
This  is  true  also  in  the  Dockum  of  Texas.  Of  the  underlying  strata 
in  northern  New  Mexico  we  cannot  be  so  certain,  as  they  are  largely 
arkoses.  The  basal  members  of  the  Manzano  group  contain  some  lime- 
stones, but  M.  G.  Girty  states  that  the  fossils  are  not  well  preserved, 
which  suggests  erosion  on  the  sea  floor  before  entombment. 

In  the  southern  part  of  New  Mexico,  the  occurrence  of  the  limestones 
and  bituminous  shales  of  the  Guadalupe  Group  at  the  base  of  the  Triassic 
and  the  great  thickness  of  limestones  in  the  Manzano  (Hueco)  suggests 
the  presence  of  petroleum;  these  same  rocks  are  probably  the  source 
of  the  oil  in  the  artesian  wells  of  the  Roswell  area. 

It  is  perhaps  well  to  bear  in  mind  that  the  criterion  that  White  sug- 
gests concerning  the  state  of  metamorphism  of  the  coals  in  an  area  is 
applicable  but  locally  in  the  Rocky  Mountains.  We  are  confronted 
there  with  exceedingly  rapid  structural  changes,  and  it  is  along  the  axes 
of  these  changes  that  the  coal  fields  White  has  mentioned  occur.  Recent 
investigations  by  Richardson,  Lee,  and  Ziegler  have  changed  our  con- 
ception of  Rocky  Mountain  structure.  The  steep  monoclines  that  form 
the  mountain  front  die  out  abruptly  both  east  and  west,  and  seem  in 
some  cases  to  have  been  accompanied  by  strike  faults.  The  zone  of 
intense  folding  is  therefore  narrow  and  is  frequently  associated  with 


198       GENETIC   PROBLEMS   AFFECTING   SEARCH   FOR   NEW   OIL   REGIONS 

volcanic  activity.  Along  the  flanks  of  these  sharp  folds  most  of  the  pro- 
ducing Rocky  Mountain  coal  fields  are  grouped;  here,  too,  there  is  the 
maximum  metamorphic  effect,  so  that  the  coals  are  of  high  grade.  As 
we  pass  from  the  folding,  the  coal  becomes  poorer  and  poorer.  The 
coals  in  the  Trinidad  field  are  associated  with  the  intrusives  of  the 
Spanish  Peaks  group,  the  coals  of  the  Durango  field  with  the  intrusives 
of  the  San  Juan  group,  the  coals  of  Crested  Butte  with  the  Crested 
Butte  intrusives,  and  those  of  the  Anthracite  Range  with  the  Elkhead 
Mountain  intrusives.  This  connection  is  surely  not  accidental.  In 
one  case,  however,  at  New  Castle,  the  high-grade  coals  are  not  associated 
with  eruptives  but  with  sharp  folding  alone.  (Basalt  flows  are  present 
in  the  near  vicinity  but  I  am  speaking  here  of  intrusives).  If  now  we 
pass  from  the  focus  of  folding  and  igneous  activity  but  a  short  distance, 
the  grade  of  the  coal  changes  markedly,  and  in  accordance  with  White's 
theory.  We  musJb,  therefore,  restrict  this  criterion  of  the  fuel  ratio  of 
the  associated  coals  to  the  locality  in  which  the  coals  occur  and  cannot 
extend  it  generally  to  formations  beyond  the  field  in  which  the  high 
fuel  ratio  coals  occur.  Further  than  this,  if  petroleum  migrates  up 
the  flank  of  Rocky  Mountain  monocline,  we  would  expect  even  within 
the  metamorphic  areas  petroleum  that  had  migrated  from  farther  down 
the  slope  where  unmetamorphosed  sediments  occur,  unless  the  metamor- 
phism  has  reached  a  point  where  the  porosity  of  the  strata  through  which 
it  must  migrate  has  been  affected.  Lighter  oils  would,  however,  be 
expected,  as  the  long  journey  would  result  in  the  fractionation  of  the 
original  oil. 

In  connection  with  the  origin  of  petroleum,  it  is  interesting  to  note 
that  almost  all  the  Cretaceous  oil  of  Wyoming  is  produced  from  the 
lower  Colorado  group,  and  that  the  oil  sands  are  directly  associated  with 
the  bituminous  shales  of  the  Mowry  and  equivalent  formations. 


PETROLIFEROUS  PROVINCES  199 


Petroliferous  Provinces  * 

BY  E.  G.  WOODRUFF,  f  TULSA,  OKLA. 
(Chicago  Meeting,  September,  1919) 

THE  earlier  struggles  in  petroleum  geology  were  directed  to  solving 
the  origin  and  method  of  accumulation  of  petroleum.  We  are  now 
fairly  well  agreed  on  those  subjects.  Most  of  us  think  that  the  great 
mass  of  petroleum  commercially  produced  comes  from  plants  or  animals, 
or  possibly  from  both.  We  are  confident  that  the  oil  was  not  produced 
where  it  is  now  found  but  has  accumulated  in  reservoirs  of  various  kinds. 
The  types  of  reservoirs  are  certainly  variable  but  they  just  as  certainly 
follow  definite  geologic  laws.  Some  of  these  types  of  reservoirs  can  be 
determined  from  surface  study;  others  cannot.  We  know,  too,  that  these 
types  of  reservoirs  (largely  structures  such  as  anticlines,  domes,  and 
terraces)  are  much  more  widespread  than  the  oil  pools.  In  other  words, 
there  are  many  places  where  good  sands  and  good  structures  exist  but 
where  oil  is  not  found.  It  is  the  purpose  of  this  paper,  therefore,  to 
attempt  to  analyze,  from  a  regional  standpoint,  some  of  the  conditions 
that  control  the  presence  or  absence  of  oil  pools  and  to  group  them  in  a 
regional  way,  hence  the  term  "Petroliferous  Provinces."  The  paper 
lays  no  claim  to  presenting  new  facts  but  attempts  to  group  and  classify 
the  information  that  so  many  have  expressed  again  and  again. 

The  essential  factors  for  an  oil  field  are  petroleum,  a  reservoir  material, 
and  conditions  under  which  the  petroleum  can  enter  the  reservoir  but 
cannot  escape  except  through  the  drill  holes.  The  paper  will  first  dis- 
cuss the  source  of  petroleum  as  it  occurs  in  definite  regions,  then  the 
regional  arrangement  of  reservoir  strata,  and  finally  the  areal  arrange- 
ment of  structures. 

To  have  petroleum,  there  must  be  a  source.  Since  living  matter 
is  considered  the  source  of  the  petroleum,  geological  conditions  must 
have  been  such  that  living  organisms  were  abundant.  Arid  regions 
on  the  earth's  surface  have  not  given  rise  to  living  things  in  sufficient 
abundance  to  produce  oil;  similarly,  too  cold  regions  and  saline  inland 
lakes.  The  converse  of  this  is  that  warm  moist  conditions  must  prevail 
to  produce  an  abundance  of  vegetable  matter.  Before  an  area  can  be 

*  Paper  prepared  for  meeting  of  Tulsa  Section,  Feb.  25  and  26,  1919. 
t  Chief  Geologist,  Oklahoma  Producing  and  Refining  Co. 


200  PETROLIFEROUS  PROVINCES 

considered  a  petroliferous  province,  it  must  have  had  an  abundance  of 
living  things  from  which  the  oil  could  have  been  derived.  On  this  basis, 
certain  classes  of  petroliferous  provinces  may  be  distinguished. 

Igneous  Rocks. — It  is  evident  at  once  that  petroleum  cannot  come 
from  provinces  in  which  there  are  nothing  but  igneous  rocks.  One  does 
not  expect  petroleum  in  the  granite  regions  of  the  Rocky  Mountains 
or  the  Hudson  Bay,  large  areas  in  western  Georgia,  North  and  South 
Carolina,  central  Maryland,  southeastern  Pennsylvania,  and  north- 
eastern New  York.  If  life  was  ever  abundant  in  these  provinces,  the 
remains  have  been  eroded  away.  They  are  certainly  non-petroliferous 
areas. 

Metamorphic  Rocks. — Organisms  may  have  been  abundant  in  the 
rocks  from  which  the  metamorphics  came  but  the  geologic  processes  are 
such  that  the  petroleum  must  have  been  driven  from  the  rocks  if  there 
was  ever  any  in  them.  Geologists  exclude  these  areas  of  metamorphic 
rock  from  the  petroliferous  provinces,  because  there  can  be  no  source 
for  the  oil  in  them. 

Sedimentary  Strata. — Almost  any  sedimentary  rock  may  be  a  source 
of  petroleum  but  to  the  commercial  geologist  some  are  impossible 
of  petroleum  production,  whereas  others  are  improbable  and  others 
probable. 

Lower  Paleozoic  Strata. — The  very  old  sedimentaries,  pre-Cambrian, 
Cambrian,  and  Ordovician,  have  not  been  productive  of  petroleum  to 
any  considerable  extent.  It  is  probably  because,  during  those  ages  of 
the  earth,  life  was  not  sufficiently  abundant  to  accumulate  in  quantities 
large  enough  to  produce  petroleum  in  commercial  quantities.  Possi- 
bly, too,  the  geological  forces  have  been  operative  so  long  and  locally 
so  intensively  that  the  petroleum  has  been  driven  from  the  strata  if  any 
ever  existed  in  them.  On  this  basis,  we  look  with  doubt  on  a  large  part 
of  Arkansas,  part  of  Missouri,  certain  areas  in  Ohio,  Tennessee,  Kentucky, 
most  of  Minnesota  and  Wisconsin,  northern  Illinois,  the  belt  of  closely 
folded  strata  from  northeastern  Alabama  to  New  York,  and  practically 
all  of  New  England.  By  this  process  of  elimination,  possible  petroliferous 
provinces  are  greatly  restricted. 

Middle  Paleozoic. — The  Middle  Paleozoic  strata  have  been  produc- 
tive but  have  produced  only  locally.  It  is  probable  that,  by  that  geolog- 
ical time,  the  animal  life  had  become  sufficiently  abundant  locally  but 
only  in  the  most  favorable  localities  to  be  a  source  for  the  oil;  therefore, 
if  the  province  under  consideration  has  only  Silurian  or  Devonian  strata  it 
should  be  considered  and  probably  classed  from  the  standpoint  of  the 
life  condition  that  prevailed  during  the  period  of  deposition.  If  the 
paleogeographic  conditions  were  such  that  life  was  abundant,  the  prov- 
ince may  be  petroliferous;  but  if  life  could  not  abound,  then  the  prov- 
ince must  be  non-petroliferous. 


B.  G.  WOODRUFF  201 

Carboniferous  and  Younger  Strata. — The  upper  Paleozoic  and  all 
younger  strata  must  be  classed  as  possibly  petroliferous.  But  in  classify- 
ing provinces  embracing  these  strata,  a  criterion  that  should  be  applied 
is  the  presence  or  absence  of  such  paleogeographic  conditions  as  supported 
life  in  abundance  or  suppressed  it.  Largely  on  this  basis  the  writer  has 
tentatively  classed  areas  in  Iowa,  Nebraska,  Kansas,  and  Arkansas  as 
non-petroliferous.  He  is  fully  aware  that  the  facts  are  as  yet  meager  and 
incompletely  studied  and  that  petroleum  may  be  produced  in  some  of 
them,  but  certainly  they  must  be  considered  doubtful.  Areas  classed 
as  promising  on  this  basis  are  in  Pennsylvania,  West  Virginia,  Kentucky, 
Tennessee,  Alabama,  Ohio,  Indiana,  Illinois,  Kansas,  Oklahoma,  and 
Texas.  Even  some  of  these  must  be  classed  as  non-petroliferous  on  the 
basis  considered  later  in  this  paper. 

Our  second  broad  division  in  classifying  any  province  as  petroliferous 
or  non-petroliferous  is  the  character  of  the  reservoir  stratum.  As 
we  know,  the  most  reliable  stratum  is  a  sandstone,  its  continuity  of 
porosity  and  the  resistance  to  closing  of  pores  under  compression  render 
it  the  most  reliable;  next  to  the  sandstone  is  porous  limestone  or  dolomite; 
and,  finally,  shale.  Other  classes  of  reservoirs  are  practically  negligible 
because  the  amount  of  oil  reservoired  in  them  is  very  small. 

The  ability  of  a  sandstone  to  reservoir  petroleum  depends  on  its 
freedom  Irom  material  that  will  fill  the  pore  spaces.  This  may  be  diffi- 
cult to  prophesy  in  advance  of  actual  drilling,  but  we  can  achieve  a 
considerable  degree  of  success  by  studying  the  conditions  under  which  the 
material  was  deposited.  Sandstone  composed  of  quartz  derived  from 
the  granites  must  be  open,  if  deposited  in  fresh,  or  comparatively  fresh, 
water  not  far  from  the  source.  On  the  other  hand,  if  the  sand  has  been 
transported  a  long  distance  from  the  source  or  deposited  in  land-locked  or 
very  saline  basins,  its  pore  spaces  are  filled  and  it  cannot  become  a  reser- 
voir stratum.  As  a  concrete  example,  the  sandstones  now  forming  along 
the  rivers  debouching  from  the  front  range  of  the  Rocky  Mountains  are 
almost  universally  porous  but  none  of  us  will  expect  the  sandstones  form- 
ing in  Great  Salt  Lake  to  be  porous.  My  associates  who  studied  the 
petroleum  conditions  of  Cuba  found  the  sand  there  to  be  derived  largely 
of  fragments  of  gabbro  from  the  great  gabbro  masses  nearby.  Appar- 
ently, these  fragments  were  fresh  when  deposited  as  sand  but  after  deposi- 
tion they  disintegrated  sufficiently  to  allow  enough  clay  to  fill  the  pore 
spaces  and  compact  the  whole  mass,  thus  closing  the  porosity  of  the 
sand  and  preventing  it  from  becoming  a  reservoir  stratum.  Some  sand 
reservoirs  are  derived  by  the  disintegration  of  previously  deposited 
sandstones,  such  as  the  Tertiary  sands  along  the  Texas  Gulf  Coast.  They 
follow  the  same  laws  as  the  sands  deposited  primarily  from  the  granites. 

Thus,  the  basis  on  which  to  classify  sand  reservoirs  must  rest  on 
paleogeography  or  on  the  character  of  the  sand  and  the  relation  of  the 


202  PETROLIFEROUS   PROVINCES 

present  position  of  the  sand  to  the  source.  Let  us  look  at  it  in  another 
way.  Take  the  map  of  the  oil  fields  of  the  United  States,  with  the 
possible  exception  of  the  Gulf  Coast;  in  the  fields  in  which  sandstones 
are  productive,  the  sandstone  beds  were  laid  down  just  off  the  flanks  of 


LEGEND. 

Pel-roll farous    Provinces. 

Areas  in  which  onlu  non-p«S 
roliferous   sedim«nvs  occur. 
Ar««s  in  which  sedimentar 
atrucrural  condition* 
are    unfavorable. 


FIG.  1. — MAP  OP  NORTH  AMERICA  SHOWING  PETROLIFEROUS  PROVINCES. 

paleozoic  mountains.  The  converse  of  this  is  that  sands  far  from  their 
source  are  not  productive  because  the  pore  space  is  closed  by  clay  or  salts. 
The  writer  feels  that  even  the  Gulf  Coast  fields  are  an  apparent  exception 
only  because  those  sands  are  secondary  and  derived  from  the  breaking  up 


E.    G.   WOODRUFF  203 

of  strata  not  far  away.  On  the  basis  of  sand  study,  the  petroliferous 
provinces  outlined  on  the  accompanying  map  are  presented. 

With  our  present  very  limited  knowledge  of  the  condition  of  limestones 
underground,  no  reliable  classification  of  provinces  can  be  made.  Some 
geologists  have  presented  data  to  show  that  the  limestones  are  cavernous 
or  porous,  whereas  others  have  shown  that  they  are  creviced  only.  At 
present  we  must  consider  all  limestone  possibly  capable  of  reservoiring 
petroleum  until  proved  otherwise,  but  the  writer  clings  to  the  idea  that 
the  time  will  come  when  certain  provinces  will  be  delimited  in  which 
the  limestones  will  be  known  to  be  non-petroliferous  because  the  lime- 
stones are  non-porous  or  non-creviced. 

The  writer  is  beginning  to  feel  that  possibly  one  distinction  may  be 
made,  based  on  the  purity  of  the  limestone,  which,  of  course,  again  de- 
pends on  the  paleogeographic  conditions  that  prevailed  when  it  was 
deposited.  The  limited  number  of  petroliferous  limestone  cuttings 
that  have  come  under  the  writer's  observation  are  very  siliceous  (generally 
cherty).  The  writer  is  inclined  to  believe,  though  he  is  not  ready  to 
apply  it  as  a  criterion,  that  only  cherty  limestone  beds  produce  petroleum 
in  commercial  quantities.  The  crevices  in  shale  offer  a  very  limited 
reservoir  space,  so  limited  in  fact  that  shale  beds  as  such  must  always  be 
considered  as  having  doubtful  commercial  petroleum  value. 

If  the  third,  but  probably  the  most  important,  set  of  criteria  to  be 
applied  in  delimiting  petroliferous  provinces  is  structure,  the  types  of 
structure  necessary  for  the  accumulation  of  petroleum  have  been  so 
thoroughly  discussed  that  a  repetition  is  unnecessary.  These  structures 
are  the  results  of  tectonic  forces  and  are,  therefore,  grouped  according  to 
certain  laws.  Again  we  are  without  sufficient  data  on  which  to  base  a 
grouping  of  these  structures.  Certainly  structures  are  most  numerous 
on  the  periphery  of  the  great  structural  basins.  They  are  not  too  close 
to  the  mountains  surrounding  the  basins  but  certainly  not  far  away. 
They  seem  to  bear  a  certain  zonal  arrangement. 

To  apply  these  criteria  a  set  of  maps  may  be  constructed:  first,  to 
show  the  petroliferous  provinces  on  the  basis  of  geologic  age;  then  to 
restrict  the  petroliferous  provinces  thus  outlined  by  striking  from  them 
the  overlapping  parts  of  the  non-petroliferous  provinces  on  the  basis  of 
reservoir  material;  and,  finally,  to  restrict  on  the  basis  of  structural 
groupings.  On  these  bases  the  writer  presents  the  accompanying  map 
of  North  America.  He  recognizes  that  it  is  imperfect  but  hopes  that  it 
may  form  a  basis  on  which  an  accurate  map  may  be  constructed. 

This  map  shows  petroliferous  provinces  as  follows: 

1.  In  Western  Alaska.     Oil  seeps  are  known  in  this  province;  there 
has  been  some  drilling  but  as  yet  no  considerable  production. 

2.  In  Western  Canada  from  the  Arctic  Ocean  to  and  including 


204  PETROLIFEROUS  PROVINCES 

Canada.     Some  commercial  production  may  be  found  in  the  northern 
part  of  this  province;  the  southern  part  is  of  doubtful  value. 

3.  Along  the  Pacific  Coast  in  California,  Oregon,  and  Washington. 
Only  the  southern  part  of  this  province  seems  important. 

4.  In  Wyoming,  Colorado,  and  a  part  of  New  Mexico.     Only  small 
areas  in  this  province  will  be  productive. 

5.  In  Oklahoma,  Texas,  and  Louisiana.     Considerable  areas  in  this 
province  are  productive  and  others  probably  will  be  found. 

6.  From  Pennsylvania  to  and  including  Illinois  and  extending  south- 
ward into  northern  Alabama  and  Mississippi. 

7.  In  Lower  California.     This  province  seems  of  doubtful  value  but 
may  be  productive. 

8.  On  the  eastern  coast  of  Mexico. 

These  are  the  broader  subdivisions  of  North  America.  On  the  same 
basis  and  by  the  same  methods  each  province  may  be  subdivided  in 
areas  in  which  petroleum  may  be  found  and  thus  a  set  of  maps  built  up 
that  will  limit  the  areas  in  which  the  geologist  and  prospector  may  hope 
for  success.  Then,  as  our  knowledge  is  perfected,  the  principles  may  be 
applied  to  South  America,  Europe,  Asia,  Africa,  and  Australia,  thus 
greatly  aiding  pioneer  work  in  those  countries  and  rendering  the  fuller 
application  of  geology  immensely  valuable  in  the  ultimate  development 
of  the  world's  petroleum  resources. 

DISCUSSION 

CHARLES  SCHUCHERT,*  New  Haven,  Conn,  (written  discussion). — 
I  embrace  the  opportunity  to  take  part  in  a  discussion  of  Mr.  Woodruff's 
paper  because  a  successful  discerning  of  what  actually  constitutes  petro- 
liferous areas  from  the  geologists'  standpoint  is  worthy  of  our  endeavors, 
not  only  from  the  intellectual  side,  but  also  because  it  may  lead,  as  Mr. 
Woodruff  hopes,  to  the  more  certain  establishment  of  principles  that 
can  be  applied  to  other  continents  in  exploiting  them  for  petroleum. 
This  discussion  will  also  embrace  the  results  of  two  other  recent  papers, 
one  by  Alexander  W.  McCoy  and  one  by  Maurice  G.  Mehl.1 

Sources  of  Petroleum. — Mr.  Woodruff  is  agreed  that  petroleum  comes 
from  plants  and  animals,  or  possibly  from  both,  and  that  it  has  ac- 
cumulated by  migration  into  reservoir  rocks.  These  reservoir  rocks 
must  of  course  be  porous  to  become  catch  basins  for  the  oil  and  gas, 
and  then,  too,  their  present  structures  are  variable,  as  they  occur  in 
anticlines,  domes,  terraces,  etc.  The  structures,  he  states,  are  more 


*  Curator,  Geological  Dept.,  Peabody  Museum  of  Natural  History. 

1  A.  W.  McCoy:  Notes  on  Principles  of  Oil  Accumulation.     Jnl  Geol  (1919)  27, 
252-262. 

M.  G.  Mehl:  Some  Factors  in  the  Geographic  Distribution  of  Petroleum.     Bull. 
Sci.  Lab.,  Denison  Univ.  (1919)  19,  55-63. 


DISCUSSION  205 

widespread  than  are  the  oil  pools,  and  the  same  is  true  for  the  reservoir 
rocks.  Accordingly,  there  must  be  many  good  sands  and  structures 
that  have  no  petroleum.  On  the  other  hand,  there  are  conditions  in  the 
making  of  the  hydrocarbons  that  are  not  formulated  by  Woodruff  or 
are  not  clearly  in  mind.  These  are:  Petroleum  is  not  formed  in  sufficient 
quantities  to  be  commercially  available  in  the  fresh-water  or  subaerial 
deposits  of  the  lands,  the  continental  deposits.  For  practical  purposes 
all  such  should  therefore  be  excluded,  at  least  for  the  time  being 
from  further  consideration.  Moreover,  land  climates  have  but  little 
direct  bearing  on  the  temperature  necessary  for  life  in  the  seas  where 
the  petroleums  are  formed,  because  there  is  an  abundance  of  life  in  all 
shallow,  marine  waters  of  whatever  clime.  Again,  there  has  been  abun- 
dant life  in  the  seas  of  all  times,  not  only  since  the  Cambrian,  but  ever 
since  the  Archeozoic.  The  proof  of  this  is  seen  in  the  high  state  of 
organic  evolution  attested  by  the  earliest  Paleozoic  fossils,  and  in  the 
nature  of  the  marine  formations  of  the  Proterozoic  and  Archeozoic  strata, 
with  their  high  carbon  content.  All  of  these  differences  between  us  will 
be  discussed  later. 

Areas  With  and  Without  Petroleum. — Mr.  Woodruff  is  seeking  for  the 
regional  conditions  that  originally  controlled  the  formation  of  the  hydro- 
carbons and  their  later  storage  into  oil  reservoirs.  In  this  way  he  is  led 
to  point  out  the  petroliferous  provinces.  The  conditions  that  make  for 
oil  provinces  he  holds  to  be  three: 

1.  The  source  of  petroleum  lies  in  the  end-results  brought  about 
through  the  decay  of  organisms,  and  the  preservation  of  the  residues 
is  limited  to  certain  environmental  conditions.     There  are  great  areas 
that  have  always  been  devoid  of  the  required  life  conditions,  and  others 
where  the  entombed  organic  residues  have  been  dissipated  by  the  defor- 
mational  processes. 

2.  Petroliferous  areas  are  limited  by  more  or  less  definite  characters 
in  the  oil-preserving  and  oil-storing  strata. 

3.  Petroliferous   strata   have   more   or   less   definite   deformational 
structures. 

The  ideas  which,  in  our  opinion,  lead  to  the  ascertaining  of  the  pet- 
roliferous and  non-petroliferous  rocks  of  North  America  are : 

1.  The  impossible  areas  for  petroliferous  rocks. 

(a)  The  more  extensive   areas  of  igneous  rocks  and  especially 

those  of  the  ancient  shields;  exception,  the  smaller  dikes. 
(6)  All  pre-Cambrian  strata. 

(c)  All    decidedly   folded    mountainous    tracts    older   than   the 
Cretaceous;  exceptions,  domed  and  block-faulted  mountains. 

(d)  All  regionally  metamorphosed  strata. 

(e)  Practically  all  continental  or  fresh-water  deposits;  relic  seas, 
so  long  as  they  are  partly  salty,  and  saline  lakes  are  excluded 
from  this  classification. 


206  PETROLIFEROUS    PROVINCES 

(/)  Practically  all  marine  formations  that  are  thick  and  uniform 
in  rock  character  and  that  are  devoid  of  interbedded  dark 
shales,  thin-bedded  dark  impure  limestones,  dark  marls,  or 
thin-bedded  limy  and  fossiliferous  sandstones. 

(gr)  Practically  all  oceanic  abyssal  deposits;  these,  however,  are 
but  rarely  present  on  the  continents. 

2.  Possible  petroliferous  areas. 

(a)  Highly  folded  marine  and  brackish  water  strata  younger  than 
the  Jurassic,  but  more  especially  those  of  Cenozoic  time. 

(6)  Cambrian  and  Ordovician  unfolded  strata. 

(c)  Lake  deposits  formed  under  arid  climates  that  cause  the 
waters  to  become  saline;  it  appears  that  only  in  salty  waters 
(not  over  4  per  cent.?)  are  the  bituminous  materials  made 
and  preserved  in  the  form  of  kerogen,  the  source  of  petroleum ; 
some  of  the  Green  River  (Eocene)  continental  deposits  (the 
oil  shales  of  Utah  and  Colorado)  may  be  of  saline  lakes. 

3.  Petroliferous  areas. 

(a)  All  marine  and  brackish  water  strata  younger  than  the  Ordo- 
vician and  but  slightly  warped,  faulted,  or  folded;  here  are 
included  also  the  marine  and  brackish  deposits  of  relic  seas 
like  the  Caspian,  formed  during  the  later  Cenozoic.  The 
more  certain  oil-bearing  strata  are  the  porous  thin-bedded 
sandstones,  limestones,  and  dolomites  that  are  interbedded 
with  black,  brown,  blue,  or  green  shales.  Coal-bearing  strata 
of  fresh-water  origin  are  excluded.  Series  of  strata  with  dis- 
conformities  may  also  be  petroliferous,  because  beneath 
former  erosional  surfaces  the  top  strata  have  induced  porosity 
and  therefore  are  possible  reservoir  rocks. 

(6)  All  marine  strata  that  are,  roughly,  within  100  miles  of  former 
lands;  here  are  more  apt  to  occur  the  alternating  series  of  thin- 
and  thick-bedded  sandstones  and  limestones  interbedded  with 
shale  zones. 

Experience  has  shown  that  commercial  quantities  of  petroleum  do 
not  occur  in  areas  of  igneous  rocks,  nor  in  regions  of  highly  folded,  mashed, 
and  decidedly  metamorphosed  strata  that  as  a  rule  are  older  than  the 
Tertiary.  Nevertheless,  it  will  not  do  to  say,  because  strata  are  decidedly 
folded  and  faulted,  that  in  the  areas  of  mountains  there  can  be  no  commer- 
cial quantities  of  oil,  for  we  know  that  the  petroleum  fields  of  the  Coast 
ranges  of  California  and  those  of  the  trans-Caspian  countries  have  yielded 
vast  quantities.  Here,  however,  the  oil-yielding  strata  are  essentially 
of  Cenozoic  age.  It  appears  that  the  main  regions  for  oil  production  in 
North  America  will  be  the  more  or  less  flat-lying  sedimentary  formations 
—the  vast  geologically  neutral  area — to  the  east  of  the  Rockies  and  to 
the  west  of  the  Appalachians.  Also,  in  a  broad  and  general  way,  the 


DISCUSSION  207 

older  the  geologic  formations,  the  more  devoid  they  are  apt  to  be  of  pe- 
troleum; and  the  more  often  a  given  area  has  been  subjected  either  to 
mountain  folding  or  to  broadly  warping  movements,  the  more  certain 
it  is  that  all  or  most  of  the  volatile  hydrocarbons  have  been  dissipated. 
Such  places  are  apt  to  have  the  hydrocarbons  only  in  fixed  form  and  not 
as  kerogen.  In  strata  older  than  the  Cretaceous,  the  deformed  geologic 
structures  of  varying  sorts  should  be  rather  of  minor  than  of  major 
strength  as  an  essential  to  oil  accumulation  in  commercial  quantities. 

Original  Oil  Strata. — It  appears  that  zones  of  petroleum,  in  general, 
do  not  occur  in  thick  deposits  that  are  continuously  of  the  same  kind  of 
material,  as  sandstones,  limestones,  or  shales,  but  in  or  near  sandstones 
and  thin-bedded  porous  limestones  that  are  interbedded  with  bituminous 
shales.  McCoy  says  that  in  the  mid-continent  field  the  petroliferous 
shales  "are  generally  dark  colored,  often  black,  and  carry  bands  of  highly 
bituminous  material."  Such  bands  "are  often  described  by  the  drillers 
as  coal,  asphalt,  or  black  lime,  according  to  the  hardness  and  appearance 
of  the  material.  The  shales  are  typical  oil  shales,  quite  similar  in  char- 
acter to  those  (of  the  Cenozoic)  of  Colorado  and  Utah." 

Petroleum  of  Organic  Origin. — The  hydrocarbons  are  the  chemical 
end-results  of  organisms  and,  in  the  main,  are  the  fatty  substances  de- 
rived through  bacterial  decomposition  from  the  plants  and  animals  once 
living  in  the  sea  waters.  This  is  a  conclusion  not  always  clearly  in  the 
minds  of  petroleum  geologists. 

One  is  led,  Dalton2  states,  "to  regard  the  great  majority  of  oils  as 
derived  from  the  decomposition  during  long  ages  at  comparatively  low 
temperatures  of  the  fatty  matters  of  plants  and  animals,  the  nitrogenous 
portions  of  both  being  eliminated  by  bacterial  action  soon  after  the  death 
of  the  organism.  The  fats  and  oils  from  terrestrial  fauna  and  flora  may 
have  taken  part  in  petroleum  formation,  but  the  principal  role  must,  from 
the  nature  of  most  petroliferous  deposits,  have  been  played  by  marine 
life." 

The  decomposition  bacteria  attack  the  cellulose  of  the  plants  and  the 
nitrogenous  tissues  of  animals,  leaving  untouched  the  fatty  materials. 
The  reason  why  the  fats  remain  untouched  is  probably  because  the  feeding 
of  the  bacteria  is  stopped  by  sedimentation,  which  buries  and  kills  the 
decomposing  organisms  living  beneath  the  surface  of  the  sea  bottom. 
Dalton  further  states  that  "Peckham's  view,  that  asphaltic  oils  are 
mainly  of  animal  origin,  while  paraffin  is  largely  derived  from  vegetables, 
is  worthy  of  acceptance  on  general  chemical  as  well  as  geological  grounds, 
since  Kramer  and  Spilker,  and  others,  have  shown  that  vegetable  fats 
produce  paraffin  either  with  or  without  artificial  distillation,  and  the 
limestone  oils,  which  on  geological  grounds  are  generally  held  to  be  mainly 

2  Leonard  V.  Dalton:  On  the  Origin  of  Petroleum.     Econ.  Geol  (1909)  4,  603-631. 


208  PETROLIFEROUS  PROVINCES 

of  animal  origin,  are  notably  asphaltic."  In  general,  the  Palaeozoic 
petroleums  have  paraffin  bases,  and  it  seems  probable  that  all  those  de- 
rived from  black  petroliferous  shales  are  largely,  if  not  wholly,  of  marine 
algal  origin.  Usually  we  do  not  realize  the  extraordinary  importance 
and  abundance  of  plant  life,  but  when  we  think  that  all  animals  are  in  the 
ultimate  dependent  for  their  existence  upon  plants,  we  begin  to  perceive 
the  truth  of  the  following  forceful  statement  by  the  English  botanist, 
F.  F.  Blackman,3  who  recently  said  that  "Botany,  as  the  science  of  plants, 
claims  dominion  over  some  99  per  cent,  of  the  living  matter  on  the 
surface  of  the  earth  and  over  most  of  the  fossil  remains  under  the 
surface." 

Petroleum  Essentially  of  Marine  Origin. — It  is,  however,  plain  to  all 
who  have  looked  into  the  matter  that  petroleums  cannot  accumulate 
upon  the  dry  land  in  deserts,  grassy  plains,  or  forests,  for  here  the  oxidiz- 
ing influences  are  so  active  that  all  the  volatile  parts  must  be  taken  away 
or  completely  changed.  In  lakes,  organic  decay  is,  as  a  rule,  so  rapid 
that  limy  marls  are  deposited,  and  it  seems  to  be  exceptional  that  black 
petroliferous  muds  are  of  fresh-water  origin.  The  extensive  oil-shale 
deposits  of  the  Green  River  series  of  Utah  and  Colorado  are  certainly 
not  of  marine  origin,  as  they  are  devoid  of  marine  organisms  and  are 
underlain  and  overlain  by  river  flood-plain  deposits  of  early  Eocene  age, 
as  is  shown  by  their  contained  land  animals  and  plants.  The  hydro- 
carbons appear  to  be  of  drifted  plant  origin,  according  to  Charles  A. 
Davis,  and  as  kerogen  does  not  form  in  large  quantities,  the  evidence 
appears  to  indicate  that  the  water  in  which  the  Green  River  shales  were 
deposited  was  slightly  saline.  Therefore  the  chemical  end-result  of  or- 
ganic decay,  the  kerogen,  cannot  accumulate  in  commercial  quantities 
except  beneath  a  sheet  of  salt  water,  and  these  sheets  of  water  probably 
are  in  the  main  within  the  limits  of  a  few  hundred  feet  of  depth;  the 
deeper  the  water  basins,  the  more  certain  the  amount  of  oil  accumulation, 
under  these  given  conditions.  Salt  water  and  organisms  are  the  first 
requisites  for  kerogen  making  in  nature  and,  accordingly,  the  hydrocar- 
bons are  stored  almost  always  in  marine  sediments;  these  are  chiefly 
the  black  and  brown  shales  and  the  impure  dark  thin-bedded  limestones. 
All  rock  formations  accumulated  directly  beneath  the  atmosphere,  as 
the  pure  continental  deposits,  must  therefore  be  devoid  of  commercial 
quantities  of  petroleum.  Then,  too,  all  deposits,  either  of  the  fresh 
waters  or  of  the  seas,  which  are  periodically  subjected  to  atmospheric 
weathering  during  their  time  of  accumulation,  are  also  lacking  in  oil  in 
paying  quantities.  Hence  we  may  further  conclude  that  all  red  or  reddish, 
yellowish  or  white,  rain-pitted  or  sun-cracked  deposit,  either  of  conti- 

*New  Phytologist  (1919)  18,  58. 


DISCUSSION  209 

nental,  fresh-water,  or  semi-marine  origin,  are  lacking  in  petroleum  in 
large  amounts. 

McCoy  informs  me  that  an  average  oil  shale  yields,  at  temperatures 
between  500°  and  1200°  F.  (260°  and  648°  C.)  about  20  gal.  (75  1.)  of  oil, 
and  from  15  to  18  Ib.  (6.8  to  8.1  kg.)  of  ammonium  sulfate  per  ton  of  shale. 
In  the  spent  shale  there  still  remains  from  15  to  20  per  cent,  of  fixed 
carbon,  but  no  ammonium  sulfate.  The  bituminous  material  in  unspent 
shales,  he  states,  "occurs  in  solid  form,  as  none  of  the  ordinary  solvents 
show  coloration  after  solution  tests.  Upon  distillation,  such  shales  have 
given  off  petroleum."  This  "solid  organic  gum  called  kerogen"  can  be 
changed  in  the  laboratory  to  liquid  hydrocarbons  by  heat.  In  nature, 
this  may  be  brought  about  possibly  by  intense  friction  developing  heat, 
but  more  probably  only  in  deep-seated  water-bearing  strata — accordingly, 
in  formations  that  are  under  greater  pressure.  However,  "  pressure  alone 
can  cause  no  change  in  this  material  when  the  included  water  is  not 
allowed  to  escape."  On  the  other  hand,  "the  maximum  static  pressure 
available  in  any  porous  zone  is  a  function  of  the  size  of  the  openings 
around  that  stratum.  The  determining  factor  is  the  capillary  resistance 
of  the  water  in  the  adjoining  small  openings."  In  other  words,  the  solid 
kerogen  "is  only  changed  to  petroleum  in  local  areas  of  differential  move- 
ment. .  .  .  After  such  a  change  is  made,  the  accumulation  of  oil  into 
commercial  pools  is  accomplished  by  capillary  water;  and  the  interchange 
only  takes  place  in  local  areas  where  the  oil-soaked  shale  is  in  direct 
contact  with  the  water  of  the  reservoir  rock.  Such  conditions  are 
explainable  either  by  joints  or  faults."  A.  B.  Thompson,  however,  in 
"Oil  Field  Development,"  states  that,  according  to  the  observations 
of  C.  W.  Washburne,  "since  water  has  a  surface  tension  of  about  three 
times  that  of  crude  oil,  capillary  attraction  exerts  about  three  times  the 
force  on  water  that  it  does  on  oil.  As  the  force  of  capillarity  varies 
inversely  as  the  diameter  of  pore,  it  is  contended  that  this  force  tends 
to  draw  water  into  the  finest  tube  in  preference  to  oil  and  displaces 
contained  oil  and  gas:  the  result  being  that  oil  would  be  expelled  from 
fine-grained  material  like  clays  into  coarse-grained  beds  like  sand." 

How  thick  must  a  petroliferous  shale  be  to  furnish  the  necessary 
amount  of  oil  for  a  productive  field?  McCoy  states  that  "the  amount  of 
oil  in  any  producing  field  could  have  been  derived  entirely  from  shales 
immediately  surrounding  the  oil  sand.  A  series  of  shales  aggregating 
10  ft.  (3  m.)  of  bituminous  sediment,  yielding  25  gal.  (94  1.)  to  the  ton, 
would  furnish  17,000  bbl.  of  oil  per  acre.  Assuming  a  25  per  cent,  ex- 
traction, the  acre  yield  would  be  over  4000  bbl.  The  average  acre  yield 
in  Oklahoma  and  Kansas  ranges  from  2500  to  3000  barrels." 

Petroleum  is  probably  forming  today  in  many  marine  waters.  Dalton 
says  it  is  present  "in  the  mud  of  the  Mediterranean  sea-floor  between 
Cyprus  and  Syria.  ...  It  was  also  found  in  the  Gulf  of  Suez,  and  in 

VOL.  LXV. 14. 


210  PETROLIFEROUS  PROVINCES 

each  case  ammonia  and  iron  sulfide  or  sulfur  occur  with  the  oil."  Po- 
tonie"  showed  its  presence  in  the  Gulf  of  Stettin,  Germany,  and  Fritsch 
showed  that  humus  is  forming  rapidly  in  the  salt  marsh  in  the  Bouche 
d'Erquy,  Brittany.  In  all  these  cases,  the  muds  are  of  the  black,  putrid 
type  that  Potonie*  calls  sapropel.  Why,  then,  does  petroleum  not  occur 
more  uniformly  in  the  geologic  deposits?  Because  the  hydrocarbons 
universally  tend  to  escape  into  the  air  or  water  from  which  they  were 
originally  taken  by  the  living  entities.  Muddy  waters  with  the  finest 
of  silts  and  not  too  much  agitated  by  currents  or  winds  are  the  places 
where  the  hydrocarbons  naturally  may  accumulate,  because  here  the 
organic  fats  and  oils  have  great  affinity  for,  and  unite  with,  the  minute 
clay  flakes,  and  are  thus  held  in  more  or  less  solid  form  and  deposited  as 
kerogen  with  the  shale  formations.  Evidently,  the  hydrocarbons  can 
accumulate  and  be  preserved  in  large  quantities  only  in  areas  of  argil- 
aceous  sedimentation.  Therefore,  in  order  to  accumulate  petroliferous 
deposits,  the  waters  must  have  life  in  them;  and  the  freer  they  are  from 
oxygen,  the  more  certain  will  be  such  accumulations.  On  the  other 
hand,  almost  all  life  fails  to  exist  where  there  is  no  oxygen,  because  oxy- 
gen is  the  first  essential  of  nearly  all  life,  and  where  the  petroliferous 
materials  are  gathering  in  greatest  quantities,  there  the  waters  are  free 
of  this  gas  and  the  bottoms  are  black  and  foul — putrid  muds  reeking  with 
odors.  Where,  then,  does  the  life  come  from  in  these  places  of  hydro- 
carbon-gathering? It  develops  in  great  abundance  in  the  sunlit,  agitated, 
and  oxygenated  surficial  areas  of  the  water  basins,  and  after  death  the 
organisms  rain  into  the  deeps,  where  they  very  slowly  decompose,  due  to 
peculiar  forms  of  bacteria  existing  in  the  stagnant  waters  that  are  de- 
pleted of  oxygen.  Are  the  surficial  waters  the  only  source  for  the  life 
that  is  gathered  into  the  oil  shales?  No.  The  life  may  develop  hun- 
dreds of  miles  away  from  the  place  of  accumulation  and  be  drifted  by 
winds,  or  by  tidal  or  even  oceanic  currents  into  bays,  cul-de-sacs  of  the 
seas,  and  into  the  shallow  but  extensive  depressions  on  the  sea  bottoms. 
The  petroliferous  deposits  are  accumulating  today  in  greatest  amount  in 
the  shallow  waters  bordering  the  lands  rather  than  in  the  greater  depths. 

However,  not  all  shales  are  oil  shales.  As  all  geologists  know,  about 
80  per  cent,  of  the  sedimentaries  are  mudstones,  and  yet  petroliferous 
shale  formations  are  not  common.  If  forced  to  guess  what  percentage 
of  shales  are  decidedly  petroliferous,  I  should  reluctantly  say  probably 
not  more  than  10  to  15  per  cent.  The  combination  of  conditions  neces- 
sary to  deposit  an  oil  shale  is  present  in  but  few  bays  or  other  deeper, 
stagnant  areas  where  clay  muds  are  collecting.  Therefore  the  import- 
ance to  all  petroleum  geologists  of  knowing  the  nature  of  the  sedimentary 
formations  of  the  areas  they  seek  to  exploit. 

The  rich  oil  shales  of  Utah  and  Colorado  appear  to  be  of  fresh-water 
origin — shallow  lakes  that  existed  in  Eocene  time.  We  are  told  that 


DISCUSSION  211 

they  yield  on  distillation  up  to  90  gal.  (340 1.)  of  oil,  about  18  Ib.  (8  kg.)  of 
ammonium  sulfate,  and  up  to  4500  cu.  ft.  (126  cu.  m.)  of  gas  per  ton  of 
shale.4  This  is  the  only  striking  occurrence  known  to  me  of  fresh-water 
deposits  in  North  America  with  an  abundance  of  hydrocarbons.  The  or- 
ganic materials  are,  in  the  main,  plants  and  their  present  condition  sug- 
gests peat  deposits.  But  we  must  again  point  out  that  the  age  of  the 
rocks  is  comparatively  recent  (Green  River  =  early  Eocene),  and  that 
they  have  undergone  but  one  slight  deformation.  Therefore  the  kerogen 
still  remains. 

Abundance  of  Life  Necessary  to  Petroleum  Gathering. — The  petroleum 
geologist  thinks  that  there  must  have  been  a  vast  abundance  of  life  to 
make  such  great  storages  of  oil  as  are  now  still  present  in  the  shales. 
In  this  he  is  undoubtedly  correct,  but  what  he  does  not  keep  in  mind  is 
the  long  time  it  has  taken  to  accumulate  the  black  shales.  Accordingly, 
the  quantity  of  life  necessary  to  oil  accumulation  need  not  be  so  vast  at  a 
given  time  as  he  thinks.  On  the  other  hand,  he  holds  that  life  did  not 
become  abundant  enough  to  result  in  petroliferous  deposits  until  Middle 
Paleozoic  time.  In  this  connection  it  should  be  said  that  paleontologists 
have  long  been  familiar  with  an  abundance  of  macroscopic  fossils  in  rocks 
dating  from  the  very  beginning  of  Cambrian  time  and  hence  from  the 
beginning  of  the  Paleozoic.  The  seas  ever  since  that  period  have  been 
filled  to  their  limit  with  life,  microscopic  and  macroscopic,  and  in  con- 
stantly increasing  variety.  What  the  geologist  sees  and  gets  are  the 
larger  fossils;  but  for  every  one  of  these  individuals  there  certainly  existed 
hundreds  of  thousands  and  probably  millions  of  invisible  plants  and  ani- 
mals. It  is  this  minute  life,  and  especially  the  plants,  that  is  so  important 
in  the  life  cycle,  for  these  microscopic  organisms  make  alive  in  their  bodies 
the  inorganic  materials  on  which  they  feed.  The  micro-plants  are  the 
basis  not  only  of  the  subsistence  of  all  the  animals  of  the  seas  and  oceans 
but,  what  is  equally  as  important,  the  accumulation  of  the  hydrocarbons. 
In  this  connection  we  may  also  add  that  the  almost  pure  chemically 
precipitated  limestones  are  due  to  the  metabolic  processes  of  minute 
plants,  the  denitrifying  bacteria.  Accordingly,  it  is  the  invisible,  and  not 
necessarily  the  visible,  fossils  that  have  gone  to  the  making  of  the  petro- 
liferous deposits  of  the  geologic  ages.  Most  of  these  forms  are  short- 
lived and  propagate  quickly  and  in  prodigious  quantities;  the  great 
majority  pass  through  the  life  cycle  in  from  a  few  hours  to  a  few  days  or 
at  most  a  few  months.  In  this  way  they  make  up  in  quantity  what  they 
lose  in  individual  size. 

We  know  of  some  animal  fossils  in  the  late  Proterozoic,  and  even 
though  they  are  as  yet  few  in  number,  their  high  organization  teaches 
unmistakably  that  there  was  a  host  of  greatly  varying  organisms.  Of 

4  Dean  E.  Winchester:  U.  S.  Geol.  Survey,  Bull  641-F  (1916). 


212  PETROLIFEROUS  PROVINCES 

lime-secreting  algal  plants  in  the  Proterozoic,  we  know  vastly  more;  and 
from  the  course  of  all  organic  evolution  as  revealed  by  the  living  world, 
supported  by  the  chronogenesis  of  the  geologic  past,  we  can  safely  state 
that  at  all  times,  even  as  far  back  as  the  beginning  of  the  Archeozoic  as 
now  known  in  the  oldest  of  geologic  deposits,  there  must  have  been  an 
abundance  of  life  in  the  waters  of  the  earth.  Hence  the  abundance  of 
graphite  in  the  Archeozoic  and  the  vast  amounts  of  dark  carbonaceous 
strata  in  the  Proterozoic.  Even  so,  it  is  hardly  probable  that  commercial 
quantities  of  petroleum  will  be  found  in  the  rocks  of  the  Proterozoic, 
and  certainly  none  at  all  in  those  of  the  Archeozoic,  because  these  very 
ancient  deposits  have  either  been  subjected  to  frequent  deformation,  or 
because,  due  to  their  great  antiquity,  the  volatile  hydrocarbons  have 
long  since  been  liberated  into  the  atmosphere. 

The  Climatic  Factor  in  Petroleum  Making. — The  question  of  land 
climates  probably  does  not  enter  at  all  into  the  matter  of  petroleum 
accumulation,  because  it  is  not  in  the  land  deposits  that  the  commercial 
quantities  of  oil  are  found.  As  has  been  said  before,  the  oils  occur  nearly 
everywhere  in  marine  deposits  and  only  rarely  in  fresh-water  ones.  This 
being  so,  and  as  the  marine  shallow  waters  of  today  abound  in  life, 
whether  in  the  warm,  cool,  or  coldest  areas,  it  follows  that  we  may  look 
for  petroliferous  formations  in  almost  all  continents  where  the  ancient 
oceans  have  spilled  over  them;  and  this  without  paying  much  attention 
to  the  changing  climates  of  geologic  time.  On  the  other  hand,  as  the 
greatest  amounts  of  carbon  and  carbonaceous  deposits  occur  in  the 
north  temperate  belt,  we  should  seek  here  in  the  main  for  the  petroli- 
ferous strata.  This  does  not  mean  that  petroleum  is  absent  in  tropical 
lands — far  from  it.  It  only  points  out  that  the  greater  quantities  will 
not  be  found  in  the  deposits  of  former  tropical  seas,  and  for  reasons  to 
be  setf  orth. 

Since  the  previous  paragraph  was  written,  there  has  appeared  the  sug- 
gestive paper  by  Mehl,  already  cited,  in  which  he  points  out  that  all  of 
the  major  oil  fields  of  the  world  are  situated  between  20°  and  50°  north 
latitude.  Further,  that  there  are  no  major  oil  areas  within  the  tropics 
or  in  the  southern  hemisphere.  As  the  known  major  oil  fields  lie  between 
the  present  isotherms  of  40°  and  70°  F.,  he  thinks  this  distribution  "does 
suggest  a  distinctly  zonal  distribution  of  petroleum  in  which  temperature 
may  have  been  an  important  factor."  The  question  that  here  arises  is,  Is 
this  suggestion  of  present  climatic  conditions  also  true  for  the  times  when 
the  oil  was  deposited  in  the  strata  in  which  it  is  now  found,  remembering 
that  the  oil  fields  were  not  made  recently  but  are  the  accumulations  of 
hydrocarbons  of  the  seas  of  the  geologic  ages?  The  answer  is  not  at  all 
in  harmony  with  MehFs  suggestion,  for  we  are  living  in  an  exceptional 
time  of  stressed  climates  and  marked  zonal  conditions,  while  the  mean 
temperature  conditions  during  the  geologic  ages  were  warm  and  equable 


DISCUSSION  213 

throughout  most  of  the  world.  And  this  is  even  more  true  of  the  tem- 
perature of  the  oceans  than  of  the  lands.  This  being  so,  much  of  the 
value  of  Mehl's  surmise  falls  away.  On  the  other  hand,  it  is  undoubtedly 
true  that  high  temperatures  in  clear  waters  and  well  oxygenated  seas 
make,  as  a  rule,  for  complete  destruction  of  the  volatile  hydrocarbons, 
while  those  of  temperate  waters  in  currentless  and  muddy  areas  tend  to 
preserve  them.  The  temperature  factor,  when  high,  appears  to  be  de- 
structive of  volatile  hydrocarbon  preservation,  but  in  this  connection  it 
should  not  be  forgotten  that  the  seas  are  far  more  equable  in  temperature 
than  are  the  lands,  and  that  during  most  of  geologic  time  the  seas  were  far 
more  equable  in  heat  content  than  they  are  today.  This  is  thought  to 
mean  that  the  ancient  tropical  seas  were  somewhat  less  warm  than  they 
are  now,  while  those  of  the  polar  areas  were  no  colder  than  the  present 
temperate  shallow-water  areas.  Corals  were  common  in  Alaska  in 
Silurian  and  Devonian  times,  corals  and  warm-water  fusulinids  lived  in 
the  Carboniferous  in  Spitzbergen,  and  there  were  magnolias  and  bread- 
fruit trees  in  Greenland  during  the  middle  Tertiary.  The  writer  also 
knows  that  hydrocarbons  have  accumulated  in  large  amounts  in  seas 
within  the  tropics,  yet  seemingly  the  amount  is  far  the  greatest  in  what 
is  now  the  north  temperate  zone.  That  this  zone  has  the  greatest  amount 
of  petroleum  is  apparently  due  wholly  to  the  greater  land  masses  here, 
along  with  the  necessary  storage  strata  accompanied  by  the  proper 
amount  of  deformation. 

Even  if  Mehl's  suggestion  were  correct,  and  we  should  accordingly 
think  of  next  exploiting  the  temperate  region  of  the  southern  hemisphere, 
we  must  not  overlook  the  fact  that  the  northern  hemisphere  is  the  land 
hemisphere,  while  the  southern  one  is  the  water  hemisphere,  and  there- 
fore has  greatly  reduced  continents.  Therefore  between  latitudes  20°  and 
50°  south  we  have  only  the  attenuated  southern  half  of  South  America,  the 
southern  tip  of  Africa,  the  southern  half  of  Australia,  and  New  Zealand. 
Southern  Africa  and  most  of  Australia  are,  furthermore,  continental 
nuclei  or  "shields"  and  therefore  have  hardly  at  any  time  been  under  the 
sea,  but  in  regard  to  South  America  the  story  of  marine  submergence  is 
very  different.  Even  now  petroleum  fields  are  known  in  Peru  ("one 
of  the  finest  oil  fields  in  the  world,"  according  to  Thompson),  Bolivia, 
and  Argentina.  Then,  too,  the  fact  should  be  emphasized  that  "shields " 
are  largely  made  up  of  pre-Cambrian  rocks  and  therefore  are  barren  of 
petroleum. 

In  regard  to  Mehl's  other  suggestion  of  a  "barren  equatorial  belt," 
I  am  inclined  to  believe  that  he  is  correct  in  the  main;  not,  however,  on 
the  ground  of  temperature  and  climate,  but  on  that  of  the  tectonic  geo- 
logic and  physiographic  conditions  of  the  continents.  On  the  other  hand, 
attention  should  be  directed  to  the  fact  that  productive  petroleum 
fields  occur  in  the  Tertiary  strata  of  the  tropical  zone  in  the  Lake  Mara- 


214  PETROLIFEROUS   PROVINCES 

caibo  area  of  Venezuela  and  in  the  Caribbean  Piedmont  of  Colombia, 
Trinidad,  and  Ecuador.  Further,  highly  productive  fields  are  those  of 
the  Indo-Malay  region,  in  Java,  Borneo,  Ceram,  and  New  Guinea.  We 
know  that  Africa  is  a  continent  that  was  more  continuously  high  above 
the  strand-line  than  any  other,  and  is  loaded  with  continental  deposits, 
while  South  America  and  more  especially  Australia  are  not  especially 
rich  in  marine  sediments,  and  when  these  are  present  they  have  been 
subjected  to  mountain-making  to  such  an  extent  that  all  of  the  volatile 
hydrocarbons  have  long  since  vanished  into  the  air  or  been  transformed 
into  fixed  carbon.  In  the  northern  hemisphere,  most  of  Asia  east  of  the 
Caspian  has  also  been  too  much  the  seat  of  crustal  movements  to  have 
much  petroleum  accumulation  in  the  Mesozoic  and  Paleozoic  formations. 
From  these  observations,  it  appears  that  the  northern  hemisphere  will 
always  remain  the  greater  for  favorable  petroleum  possibilities. 

In  all  that  has  so  far  been  said,  the  statements  relate  in  the  main  to 
folded  continental  masses, but  as  some  most  wonderful  oil  fields,  like  that 
of  the  Baku  area  in  Trans-Caucasia,  are  of  very  small  extent,  it  follows 
that  many  restricted  and  highly  productive  fields  are  possible  even  in 
areas  of  decided  crustal  movements,  but  I  should  look  for  such  places 
only  in  regions  of  Cenozoic  marine  formations,  and  mainly  in  Asia. 

Paleogeography  as  an  Aid  in  Locating  Oil  Areas. — The  importance  of 
paleogeography  in  petroleum  geology  is  as  yet  but  little  appreciated. 
Foul  sea  bottoms,  where  the  hydrocarbons  accumulate,  and  sandstones, 
in  which  they  are  stored,  are  usually  connected  with  nearness  to  land. 
Their  physical  characters  have  to  do  with  shallow  seas  and  more  espe- 
cially with  headlands,  off-shore  spits  and  bars,  barrier  beaches  and  river 
mouths,  which  divert  and  from  time  to  time  change  the  currents  of  the  sea. 
On  the  other  hand,  the  open  seashores,  with  their  more  or  less  long 
"fetch  of  the  winds,"  are  the  washeries  of  the  land-derived  detritus. 
Here  the  cliff-derived  materials  are  broken  up  by  the  waves  of  the  seas 
in  their  grinding  mills,  and  the  finer  erosion  materials  of  the  weathering 
lands,  brought  by  the  rivers,  are  assorted  and  reasserted  many  times 
according  to  specific  gravity  and  size  of  grain.  The  coarsest  material  lies 
on  the  strand  and  near  the  shore,  and  seaward  the  material  becomes, 
broadly  stated,  finer  and  finer  of  grain.  All  of  this  assorting  and  sea- 
transporting  depends  on  the  size  of  the  waves  " kicked  up"  by  the  winds, 
and  the  shallowness  of  the  waterways.  It  makes  no  difference  whether 
it  is  long  or  short  rivers  that  deliver  the  unassorted  muds  and  sands  to 
unagitated  and  stormless  seas,  the  deposits  will  be  neither  petroliferous- 
making  areas  nor  good  rock  reservoirs  for  oil.  If,  however,  such  materials 
are  delivered  into  the  open  and  stormswept  seas,  there  will  be  assorting 
according  to  size  of  grain,  and  the  sandbars  will  make  headlands  behind 
which  current-less  waters  will  accumulate  the  hydrocarbons.  In  all  this 
we  see  that  as  the  places  of  natural  hydrocarbon  manufacture  and  its 


DISCUSSION  215 

future  storage  are  conditioned  by  the  nearness  of  the  shore  and  the  depth 
of  water,  it  behooves  petroleum  geologists  to  pay  close  attention  to  the 
discerning  of  the  myriads  of  constantly  changing  geographies  of  the  geo- 
logic past. 

Petroliferous  Provinces. — We  have  now  defined  the  essential  principles 
that  underlie,  in  nature,  the  gathering  of  petroleum  in  commercial  quanti- 
ties and  can  next  consider  the  question,  What  constitutes  a  petroliferous 
province?  Clearly  it  cannot  be  merely  an  area  that  produces  oil,  because 
the  word  province  is  significant  of  embracing  things  more  or  less  of  a  kind. 
Shall  the  criterion  be  whether  the  area  has  solid  or  fluid-gaseous  hydro- 
carbons? Or  whether  the  strata  are  dry  or  wet?  Probably  neither. 
Shall  it  be  the  nature  of  the  oil,  whether  it  is  light  or  heavy?  Probably 
not.  Seemingly  it  should  rather  be  the  age  and  time  of  deformation  of 
the  strata  having  oil,  combined  with  their  governing  structures.  In 
other  words,  the  classification  should  express  the  chrono-orogenetic 
origin  of  the  oils.  For  instance,  in  the  Ohio  Basin  province,  a  subprovince 
would  be  the  oil  fields  in  the  vanishing  Appalachian  folds  along  the 
western  sde  of  the  Allegheny  area;  another,  the  eastern  Ohio  oil  fields; 
and  a  third,  the  Trenton  area  of  Ohio  and  Indiana.  A  beginning  in 
such  mapping  has  been  made  by  Johnson  and  Huntley  in  their  "  Oil  and 
Gas  Production/'  plates  91  and  92.  However,  in  the  course  of  time  we 
shall  here,  as  in  other  studies,  undergo  an  evolution  in  our  classifications. 

In  general,  Mr.  Woodruff's  map  and  plate  92  of  Johnson  and  Huntley 
bring  out  the  areas  of  worth-while  exploiting,  those  of  improbable  value, 
and  the  regions  that  can  have  no  petroleum.  However,  these  maps 
are  so  small  that  other  and  even  more  essential  features  cannot  be 
depicted;  these  are  the  structural  trend  lines,  the  periodically  rising  areas 
or  "crustal  highs,"  the  long-enduring  ancient  lands  and  their  shore-lines, 
and  whether  the  region  has  strata  of  more  than  one  era.  Of  course,  all  of 
these  things  cannot  be  plotted  on  a  single  map,  however  large,  but  until 
this  is  done  on  a  series  of  maps,  we  cannot  define  what  are  the  genetic 
characteristics  of  each  petroliferous  province  and  the  proper  guidance  to 
its  exploitation. 

The  most  important  of  all  geologic  problems  connected  with  oil 
exploitation,  the  geologic  structures,  will  not  be  discussed  here.  Among 
the  most  important  maps  necessary  for  the  broad  guidance  of  petroleum 
geologists  is  one  to  show  the  "highs"  or  positive  areas  and  the  deforma- 
tional  structure  lines,  drawn  in  symbols  according  to  geologic  age,  i.e., 
to  show  the  trends  of  the  mountain  folds,  the  many  low  axes,  like  the 
Cincinnati  axis,  and  the  greater  fault  lines.  Such  a  map,  of  even  a 
limited  area,  would  be  a  prophetic  guide  to  oil  exploitation  in  the  region 
so  mapped. 

Can  such  highly  desirable  maps  be  made  quickly?  Naturally  no  one 
geologist  can  alone  make  such  maps  of  the  North  American  continent, 


216  PETROLIFEROUS  PROVINCES 

or  even  of  the  United  States.  They  can  be  made  only  through  coopera- 
tion. A  special  commisson  for  this  work  should  be  organized  by  the 
larger  oil  companies  and  a  philosophical  study  made  of  all  of  the  geologic 
problems  involved  in  petroleum  discovery.  For  this  we  have  an  example 
in  the  study  of  the  principles  underlying  copper  genesis  made  by  the  cop- 
per-producing companies  of  the  United  States,  at  a  cost  of  about  $50,000. 
A  similar  contribution  by  the  oil  companies  would  go  far  and  might, 
even  in  a  few  years,  make  all  of  the  required  generalizing  maps.  But  will 
the  companies  believe  in  these  possible  solutions,  and  that  they  will 
undoubtedly  lead  to  a  more  certain  and  a  more  constantly  successful 
exploitation  of  petroleum  in  North  America?  We  have  faith  in  our 
prophecy,  but  will  the  operators  have  faith  in  the  prophets? 

IRVING  PERRINE,  Hutchinson,  Kans. — I  think  in  reading  this  paper 
one  should  bear  in  mind  its  relation  to  Dr.  David  White's  paper  on  "Some 
Relations  in  Origin  between  Coal  and  Petroleum."5  In  that  paper  he 
discusses  the  relationship  between  the  percentages  of  fixed  carbon  in  the 
coals,  the  gravities  of  the  oils,  and  commercial  gas  possibilities.  His 
paper  has  amap  showing  certain  areas  which  Doctor  White  believes  to  be 
hopeless  as  far  as  oil  and  gas  possibilities  are  concerned. 

THE  CHAIRMAN  (C.  W.  WASHBURNE,  New  York,  N.  Y.). — I  would 
like  to  emphasize  one  point  brought  out  by  Professor  Schuchert.  The 
southern  hemisphere  has  had  an  exceedingly  monotonous  geological  his- 
tory, except  the  northern  border  of  Africa,  the  eastern  border  of  Aus- 
tralia, and  the  western  and  northern  borders  of  South  America.  In 
other  parts  of  these  continents  there  has  been  little  deposition  of  marine 
sediments  and  very  little  deformation  since  Paleozoic  time.  Therefore 
they  are  not  attractive  places  to  the  prospector  for  oil. 

There  is  probably  truth  in  Schuchert's  idea  that  the  composition 
of  the  sea  water  may  have  had  something  to  do  with  the  preservation  of 
organic  matter.  I  followed  the  outcrop  of  an  oil  sand  about  700  kilo- 
meters along  the  western  coast  of  Africa.  The  fossils  in  it  are  exceedingly 
minute,  showing  that  the  condition  of  the  sea  water  was  not  suitable 
for  vigorous  life,  the  oysters  are  not  much  larger  than  the  head  of  a  lead 
pencil,  and  nearly  all  forms  are  dwarfs.  In  Madagascar  there  is  the 
same  formation  with  similar  faunal  conditions.  If  the  water  in  semi- 
enclosed  basins  is  very  salty  water,  bacteria  cannot  thrive  in  it  much 
better  than  the  molluscan  forms  of  life.  This  is  probably  an  indication 
that  the  composition  of  the  sea  water  in  enclosed  basins  may  have  some- 
thing to  do  with  the  preservation  of  fats  and  waxes  in  the  sediments  of 
certain  areas. 

.    6  Jnl  Washington  Acad.  Sciences  (Mar.  19,  1915). 


NATURE   OP   COAL  217 


Nature  of  Coal 

BY  J.  E.  HACKFORD,  LONDON,  ENG. 

(St.  Louis  Meeting,  September,  1920) 

IN  SOME  research  work  carried  out  by  the  writer,  certain  results  have 
been  obtained  which  bear  on  the  fundamental  nature  and  origin  of  coal 
and  the  relationship  between  coal  and  petroleum.  Without  entering 
into  a  discussion  of  the  details  of  the  experiments,  which  were  conducted 
on  petroleum  and  derived  bitumens,  there  are  given  here,  by  way  of 
definition,  some  of  the  relations  that  the  writer  has  established  between 
certain  classes  of  bitumens  of  petroliferous  origin. 

Bitumen. — A  natural  organic  substance,  gaseous,  liquid,  or  solid, 
consisting  of  hydrocarbons  and  the  oxy-or  thionic  derivatives  of  the  same, 
or  of  a  mixture  of  all  three. 

Diasphaltenes. — Those  portions  of  bitumens  that  are  soluble  in 
ether  or  carbon  disulfide,  but  are  insoluble  in  a  mixture  of  equal  parts  of 
ether  and  alcohol.  Diasphaltenes  are  produced  by  the  oxidation  or 
thionization  of  petroleum  oils;  they  have,  as  the  name  indicates,  twice 
the  molecular  weight  of  asphaltenes,  into  which  they  are  converted  when 
subjected  to  moderate  temperature.  For  example,  an  artificially  produced 
diasphaltene,  which  was  readily  soluble  in  pentane  and  ether,  was 
quite  insoluble  in  either  of  these  solvents  after  heating  for  three  weeks  at  a 
temperature  of  100°  C.,  and  was  converted  into  an  insoluble  asphaltene. 

Asphaltenes. — Those  portions  of  bitumen  that  are  insoluble  in 
ether  or  ether  alcohol  but  are  soluble  in  carbon  disulfide. 

Asphaltites. — Those  solid  or  semisolid  natural  bitumens  that  are 
composed,  for  the  most  part,  of  asphaltenes  or  diasphaltenes.  A  pure 
asphaltite1  would  be  composed  wholly  of  asphaltenes  and  diasphaltenes, 
but  most  asphaltites  contain  small  percentages  of  oil  and  wax,  which  have 
not  yet  been  converted  into  asphaltenes;  they  may  also  contain  a  small 
percentage  of  kerotenes,  which  represent  the  next  stage  of  the  metamor- 
phosis of  asphaltenes.  Among  the  naturally  occurring  oxyasphaltites 
may  be  mentioned  grahamite;  and  among  the  thioasphaltites,  gilsonite. 


1  The  term  asphaltite,  as  recommended  by  Eldridge  (22nd  Ann'jal  Report,  U.  S. 
Geol.  Survey,  1901)  is  preferable  to  Dana's  term  "asphaltum"  ("Descriptive  Mineral- 
ogy," 6th  edition,  1906,  1017),  for  the  reason  that  the  naturally  occurring  represen- 
tatives have  the  generic  ending  "-ite,"  e.g.,  gilsonite,  grahamite,  etc. 


218  NATURE   OF  COAL 

Kerotenes.' — Those  portions  of  bitumen  that  are  insoluble  in  carbon 
disulfide.  They  are  produced,  by  gentle  heat,  from  asphaltenes.  It 
can  be  demonstrated  experimentally  that  artificially  produced  thio- 
asphaltenes  and  oxyasphaltenes,  when  kept  at  a  temperature  of  100°  C. 
for  three  months,  are  converted,  with  but  slight  gaseous  losses  and  without 
change  in  sulfur  content,  into  kerotenes.2  Most  of  the  kerotenes  pro- 
duced by  gentle  heating  from  asphaltenes  in  this  manner  were  entirely 
insoluble  in  any  known  solvent,  including  pyridine,  chloroform,  and 
quinoline. 

Kerok. — Those  portions  of  kerotenes  that  are  soluble  in  chloro- 
form as  well  as  in  pyridine. 

Keroles. — Those  portions  of  kerotenes  that  are  soluble  in  pyridine 
but  insoluble  in  chloroform. 

Kerites. — Natural  solid  bitumens  composed,  for  the  most  part,  of 
kerotenes.  A  pure  kerite  would  be  composed  wholly  of  kerotenes,  but 
the  natural  kerites  generally  contain  small  percentages  of  one  or  more  of 
the  following:  asphaltenes,  diasphaltenes,  wax,  and  oil,  whose  conver- 
sion to  kerotenes  has  not  been  completed.  Of  the  natural  examples, 
wurtzilite  may  be  mentioned  as  a  thiokerite  and  albertite  as  an  oxy kerite. 

It  has  been  demonstrated,  in  the  course  of  these  experiments,  that 
either  sulfur  or  oxygen  can  play  a  predominating  role  in  the  formation 
of  these  classes  of  bitumens.  If  a  straight  Pennsylvania  lubricating  oil 
with  a  negligible  sulfur  content  is  digested  at  a  temperature  of  100°, 
with  either  sulfur  or  oxygen,  a  darkening  in  color  first  takes  place  (owing 
to  the  formation  of  thio-  and  oxydiasphaltenes) ;  this  discoloration  gradu- 
ally increases  to  black  with  the  formation  and  precipitation  of  asphalt- 
enes, which  constantly  increase  until  the  whole,  except  for  gaseous  losses, 
is  converted  into  kerotenes.  Similar  results  have  been  obtained  from 
sulfur-free  paraffme  wax3  and  from  natural  petroleum  oils  of  all  characters; 
that  is,  by  oxidation  or  thionization,  accompanied  by  gentle  heat,  any 
natural  petroleum  oil  may  be  converted  first  into  oxy-  or  thioasphaltenes 
then  into  kerotenes.  Certain  kerotenes  are  wholly  insoluble  in  any  of 

*  This  term  is  derived  arbitrarily  from  the  word  "kerogen, "  the  term  introduced 
by  Crum  Brown  (Oil  Shales  of  theLothians,  Geol.  Sur.  of  Scotland,  1912, 43)  to  denote 
the  organic  matter  present  in  oil  shales,  in  ordinary  solvents,  and  from  which  hydro- 
carbons are  obtained  by  dry  distillation.  It  was  at  first  proposed  to  use  the  term 
kerogen,  which  would  be  entirely  appropriate  in  this  general  sense,  but  it  was  felt 
that  some  confusion  might  arise  because  the  word  kerogen  has  become  associated 
with  the  bitumen  of  the  oil  shales  alone. 

8  Allen  (Pet.  Rev.,  Apr.  26,  1913)  and  Redwood  ("Treatise  on  Petroleum"  1,  275) 
consider  the  black  precipitate  formed  in  paramne  wax,  when  heated  with  sulfur,  to 
be  carbon,  but  the  writer  has  demonstrated  that  this  precipitate  dissolves  entirely 
when  heated  with  benzol;  it  therefore  cannot  be  carbon.  The  addition  of  an  excess 
of  ether  or  pentane  to  this  benzol  solution  throws  down  a  black  precipitate,  which  is 
simply  a  thioasphaltene. 


J.    E.    HACKFORD  .  219 

the  known  solvents,  including  chloroform,  pyridine,  and  quinoline. 
As  these  experiments  progressed,  it  became  evident  that  bodies  closely 
analogous  to  coal  were  being  produced  from  petroleum  in  the  laboratory 
by  oxidation,  thionization,  and  gentle  heat;  this  gave  rise  to  certain  in- 
ferences, which  it  is  the  purpose  of  this  paper  to  state. 

RESULTS  OF  PREVIOUS  INVESTIGATORS 

The  elucidation  of  the  nature  of  a  body,  like  coal,  that  is  only  sparingly 
soluble  in  solvents  and  cannot  be  made  to  yield  crystalline  derivatives 
without  previous  violent  manipulation  has  naturally  presented  no  little 
difficulty.  During  the  past  five  years  a  large  amount  of  work  has  been 
accomplished  respecting  the  nature  of  coal  by  numerous  investigators.4 

These  investigations  have  been  mainly  along  two  lines:  one  was 
the  examination  of  solvent  extracts,  and  the  other  was  the  study  of  the 
products  of  low-temperature  distillation.  The  results  are  scattered 
and  the  inter-relationships  have  not  been  fully  pointed  out.  Briefly 
stated,  the  studies  of  these  investigators  have  shown: 

1.  That  by  low-temperature  distillation  work  and  by  the  examination 
of  solvent  extracts,  paraffine,  olefines,  and  naphthenes  have  been  isolated 
and  identified. 

2.  That  the  tar  distilled  from  coal  at  high  temperatures  is  a  decomposi- 
tion  product   of   coal   tars   previously   formed   at  low  temperatures. 

3.  That  the  cellulosic  compounds  present  in  coal  result  in  the  forma- 
tion of  phenols  upon  dry  distillation. 

4.  That  the  temperature  at  which  coal  was  formed  cannot  have 
approached  300°  C. 

RELATION  OF  SOLUBLE  PORTIONS  OF  COALS  AND  KERITES 

In  1913,  Messrs.  Clark  and  Wheeler5  described  experiments  in  which 
a  soft  bituminous  coal,  upon  extraction  with  pyridine,  yielded  a  substance 
representing  by  weight  a  percentage  of  the  original  sample,  which  upon 
subsequent  low-temperature  distillation  yielded  a  mixture  of  paraffine- 
hydrocarbons  and  hydrogen.  In  view  of  his  research,  the  writer  sus- 
pected that  the  portions  of  coal  extracted  in  this  manner  by  pyridine 
consisted,  largely,  of  asphaltites  and  the  soluble  kerites;  accordingly  the 
following  experiment  was  carried  out: 

4D.  T.  Jones:  Jnl.  Soc.  Chem.  Ind.  (1917)  36,  3-7;  Jones  and  Wheeler:  Chem. 
Soc.  Trans.  (1916)  109,  707,  714;  Burgess  and  Wheeler:  Chem.  Soc.  Trans.  (1910) 
97,  1917-1935;  (1911)  99,  649,  667;  (1914)  105,  131-140;  Clark  and  Wheeler:  Chem. 
Soc.  Trans.,  103,  1704-1713;  R.  Maclaurin:  Jnl.  Soc.  Chem.  Ind.  (June,  1917); 
Pictet  and  Bouvier:  Compt.  Rend.  (1913)  167,  779-781;  Pictet,  Ramseyer  and  Kaiser: 
Compt.  Rend.  (1916)  163,  358-361;  Fischer  and  Glund:  Berichte  (1916)  49,  1469-1471; 
and  Fraser  and  Hoffman:  Tech.  Paper  5,  U.  S.  Bureau  of  Mines. 

6  Chem.  Soc.  Trans.  (1913)  113,  1704-1713. 


220 


NATURE   OP   COAL 


A  sample  of  250  gr.  of  Yorkshire  coal  was  extracted  with  pyridine.  The 
bulk  of  the  pyridine  was  then  distilled  off  under  reduced  pressure  and  a 
large  excess  of  ether  added.  A  voluminous  black  precipitate  was  thrown 
down,  which  was  pumped,  washed  with  ether,  and  weighed.  By  weight, 
it  represented  5.1  per  cent,  yield.  This  black  powder  was  found  to 
be  15  per  cent,  asphaltenes  and  84.9  per  cent,  kerotenes.  The  84.9  per 
cent,  of  kerotenes  was  found  to  be  a  combination  of  17.9  per  cent,  of 
kerols  and  67  per  cent,  of  keroles.  We  thus  succeeded  in  splitting  up 
this  black  precipitate  in  a  similar  manner  and  in  similar  fractions  to  those 
obtained  when  working  upon  natural  kerites,  as,  for  example,  albertite 
and  wurtzilite,  which  gave  the  following  results : 


OXYKERITE  THIOKERITE 
(ALBERTITE)  (WURTZILITE) 
PER  CENT.  PER  CENT. 


Asphaltenes. 
Kerotenes. . . 

Sulfur 

Oxygen 


9.0 
89.03 
Trace 

6.97 


12.8 
81.37 
5.83 
0.00 


The  similarity,  however,  does  not  end  here,  for  many  of  the  fractions 
upon  heating  melted  with  decomposition,  evolving  oil  containing  (in  the 
case  of  albertite)  quantities  of  paraffine  wax;  while  the  asphaltenes  and 
kerols  evolved  sulfuretted  hydrogen.  The  most  sparingly  soluble  frac- 
tion, keroles,  do  not  intumesce  to  any  extent  upon  heating,  as  do  the 
asphaltenes.  The  solubilities  of  these  substances  are  exactly  the  same 
as  those  similar  fractions  derived  from  natural  kerites,  e.g.  the  asphaltenes 

TABLE  1. — Analysis  of  Unfractionated  Precipitate 


Asphaltenes  and 
Kerotenes     from 
Coal 
Per  Cent. 

Natural  Kerite,  e.g. 
Albertite  from 
New  Brunswick 
Per  Cent. 

Kerite  in  a  Trans- 
former Sludge0 
Naturally  Pro- 
duced by  Oxida- 
tion of  Trans- 
former Oil 
Per  Cent. 

Synthetic     Oxy- 
kerite  Prepared  by 
Passing  Oxygen 
Through  Lubri- 
cating Oil 
Per  Cent. 

Asphaltenes  and 
kerotenes 

100 

98  03 

100 

100 

Carbon  

73.64 

76  0 

74  0 

Hydrogen. 

4  87 

7  1 

6  2 

Sulfur 

1  07 

trace 

? 

1  58 

Nitrogen  

2  83 

1.4 

? 

Oxygen 

16  67 

6  97 

16  97 

18  22 

0  Dr.  A.  C.  Michie  [Jnl  Inst.  Elec.  Engrs.  (1913)  51,  213]  gives  an  analysis  of  a 
sludge  deposited  by  a  transformer  oil  when'used  in  an  auto-starter  for  a  considerable 
period.  The  writer  has  carried  out  detailed  experiments  on  a  similar  sludge.  The 
original  oil  in  this  case  was  known  to  be  a  straight  cut  oil.  The  sludge  was  found  to 
consist  of  10.1  per  cent,  of  oxykerotenes  and  79.9  per  cent,  of  oxyasphaltenes.  The 
oxyasphaltenes,  after  gentle  heating  for  a  month,  were  converted  into  oxykerotenes, 
portions  of  which  were  insoluble. 


J.    E.    HACKFORD  221 

both  from  the  coal  and  from  a  sample  of  a  natural  kerite  were  soluble  in 
carbon  disulfide,  benzene,  phenol,  nitrobenzene,  chloroform  pyridine,  etc. 
but  were  insoluble  in  petroleum  ether,  ethyl  ether,  ethyl  alcohol. 

The  analysis  of  the  whole  unfractionated  precipitate  is  given  in  Table 
1,  and,  for  the  sake  of  clearness,  is  contrasted  with  a  natural  kerite,  a 
naturally  produced  kerite,  and  a  synthetic  kerite. 

RELATIONS  OF  INSOLUBLE  PORTIONS  OF  COALS  AND  KERITES 

It  has  been  found  that,  upon  prolonged  heating,  a  portion  of  the 
kerotenes  becomes  insoluble  in  pyridine  or  any  known  solvents;  by  in- 
ference it  is  believed  that  most  of  the  insoluble  portion  of  coal  consists 
of  a  true  bitumen  that  has  been  transformed  by  gentle  heating  into  an 
insoluble  kerotene,  and  that  a  small  portion  is  due  to  the  decomposition 
products  of  cellulose,  as  shown  by  the  formation  of  phenol  upon  dry 
distillation.6  The  writer  has  proved  that  the  kerites  experimentally 
produced  from  petroleum  yield,  at  both  low-  and  high-temperature  dis- 
tillation, exactly  the  same  products  as  are  obtained  under  the  same  tem- 
perature conditions  from  the  kerites  of  coal. 

THEORY  OF  FORMATION  AND  NATURE  OF  COAL 

The  following  theory  is  put  forward  as  to  the  mode  of  formation  and 
nature  of  coal,  comparing  it  at  the  same  time,  for  the  sake  of  clearness, 
with  the  mode  of  formation  of  oil. 

First,  consider  a  stratum  containing  a  deposit  of  either  animal  re- 
mains or  marine  vegetation.  These  substances,  on  decomposition,  form 
oil  and  gas  which,  if  contained  in  a  sandy  bed,  are  swept  away  from  their 
source  by  either  gravity  or  water  as  rapidly  as  formed,  since  neither  the 
animal  remains  nor  the  marine  vegetation  contain  cellulosic  material 
capable  of  forming  a  spongelike  mass,  which  would  hold  the  oil  in  situ 
during  the  decomposition  stage. 

Second,  assume  a  buried  deposit  of  terrestrial  vegetation.  De- 
composition takes  place,  resulting  in  the  formation  of  oil  and  gas,  as  in 
the  case  of  the  marine  vegetation.  However,  owing  to  the  cellulosic 
nature  of  the  material  and  its  porous  spongy  nature,  the  oil  is  kept  in  situ 
while  decomposition  proceeds.  Accompanying  this  decomposition, 
there  is  probably  a  rise  in  temperature,  which  even  if  not  above  100°  C. 
is  quite  sufficient,  as  we  have  proved  in  the  laboratory,  to  convert  into 
kerotenes  the  oxy-  or  thioasphaltenes  that  are  simultaneously  formed  with 
the  oil.  As  the  process  goes  on,  the  kerotenes  become  more  and  more 
insoluble  until  they  are  insoluble  in  pyridine  and  quinoline  and  so  remain 
as  a  solid  in  the  spongelike  mass  afforded  by  the  cellulosic  structure  of 
the  terrestrial  vegetation. 

6  Jones  and  Wheeler:  Chem.  Soc.  Trans.  (1916)  109,  707-714. 


222  NATUEE  OP  COAL 

It  has  been  recorded  by  Hodgland  and  Lief7  that  the  algae  on  which 
they  made  tests  contained  from  5  to  13  per  cent,  of  sulfur.  It  therefore 
follows  that  in  those  coals  that  contain  algal  ingredients  in  quantity,  some 
undoubted  cases  of  which  White8  puts  on  record,  a  larger  amount  of  thio- 
bitumens  should  be  present  with  a  corresponding  reduction  in  the  oxy- 
bitumens  and  the  cellulosic  residues. 

According  to  this  theory,  the  amount  of  soluble  bitumens  should  be 
greatest  in  peat  and  should  decrease  through  lignite,  sub-bituminous, 
bituminous,  and  semibituminous  coals  to  anthracite,  which  indeed  is  the 
case.  It  is  interesting  to  note  that  where  pure  kerite  deposits  have  been 
found,  they  have  nearly  always  been  mistaken  for  coal.  It  took  ten 
years'  litigation  to  decide  whether  the  New  Brunswick  oxykerite  was  coal 
or  bitumen.  Similar  instances  are  given  by  L.  L.  Hutchison9  in  the  case 
of  the  Jackfork  Valley,  the  Impson  Valley,  etc.  A  similar  case  of  a  thio- 
kerite  is  a  deposit  in  Nova  Zembla,  where  coal  suitable  for  metal  smelting 
was  reported  to  be  situated  near  an  ore  deposit.  Samples  of  this  deposit 
were  forwarded  to  the  writer  and  yielded  on  analysis:  ash,  0.72  per  cent.; 
sulfur,  15.54  per  cent.;  nitrogen,  0.76  per  cent.  The  sample  possessed 
a  bright  luster  and  had  the  appearance  of  a  bright  soft  coal.  It  was, 
however,  totally  insoluble  in  solvents  and  on  heating  gave  off  little  gas. 
No  oil  whatever  was  evolved;  in  fact,  the  sample  behaved  in  nearly 
every  respect  like  anthracite.  The  volatile  matter  was  only  1.8  per 
cent.  However,  from  a  comparison  with  certain  experiments  then  in 
progress,  it  was  decided  that  the  material  was  a  kerite.  A  subsequent 
geological  examination  showed  the  deposits  to  occur  in  small  lenses  in  a 
metamorphosed  deep-sea  limestone,  which  contained  none  of  the  depo- 
sitional  associate  of  coal  and,  in  fact,  confirmed  the  oil  origin  of  the 
deposit.  This  is  regarded  as  a  pure  sample  of  a  thiokerite.  It  is 
probably  true  that  certain  so-called  coals  from  Colombia  that  have  a 
sulfur  content  of  13  per  cent,  are  simply  thiokerites. 

The  main  differences  between  these  so-called  coals  and  true  coal  rests 
in  the  fact  that  they  possess  no  cellulosic  residue,  which  upon  distilla- 
tion can  produce  phenols,  as  is  the  case  in  true  coals.  It  is  conceivable 
that  a  kerite  produced  from  microscopic  vegetal  remains  containing  some 
cellulose — but  not  in  sufficient  quantities  to  act  as  a  sponge — would  yield 
phenols  on  dry  distillation;  this  would  be  but  another  connecting  link 
between  coal  and  petroleum. 

Petroleum  oils,  such  as  occur  in  nature,  are  clearly  not  derived  from 
coal;  but  given  a  quantity  of  vegetal  material,  petroleum  may  be  pro- 
duced under  a  given  set  of  circumstances  if  no  cellulose  is  present  and 
coal  will  be  formed  if  the  vegetal  matter  contains  sufficient  cellulose  to 
form  a  sponge. 

7  Jnl  Biol  Chem.  (1915)  23,  287-297. 

8  David  White:  TJ.  S.  Geol.  Survey  Bull  29,  48  et.  seq. 

9  Oklahoma  Geol.  Survey  Bull  2,  81-89. 


DISCUSSION  223 

DISCUSSION 

W.  E.  PRATT,  *  Houston,  Tex. — Mr.  A.  W.  McCoy  some  time  ago,  after 
pressing  or  squeezing,  extracted  oil  with  ether  from  oil-shales  which  before 
squeezing  yielded  no  oil  upon  extraction.  Mr.  C.  W.  Washburne,  in 
discussing  McCoy's  results,  attributes  the  formation  of  oil  in  the  shale 
to  heat  induced  by  pressure  rather  than  to  pressure  directly.  This  seems 
to  be  McCoy's  idea  also;  that  is,  the  ether-soluble  content  increased  upon 
the  application  of  heat  (through  pressure).  Mr.  Hackford  finds  that 
similar  materials  which  have  a  certain  ether-soluble  content  suffer  a 
decrease  in  ether-soluble  content  through  the  direct  application  of  heat. 
There  is  an  apparent  contradiction  in  this  situation  which  may  be 
explained,  perhaps,  by  assuming  that  heating  "cracked  off"  new  ether- 
soluble  combinations  in  each  set  of  experiments,  but  that  these  new 
compounds  were  allowed  to  escape  in  Mr.  Hackford's  work,  leaving  the 
residual  material  less  ether-soluble,  whereas  Mr.  McCoy  retained 
the  cracked  products  in  the  original  material  until  he  extracted  them 
with  ether. 

DAVID  WHITE,  Washington,  D.  C. — The  theory  that  beds  of  coal  are 
bituminized  from  outside  sources  is,  I  believe,  to  be  regarded  with  great 
skepticism.  That  the  bitumens,  so  called,  are  generated  in  the  process  of 
the  evolution  of  the  coal  bed  itself  appears  more  tenable,  and  will,  I 
anticipate,  be  ultimately  proved. 

The  distinction  between  the  origin  of  the  normal  series  of  coals,  namely 
from  terrestrial  or  vascular  vegetation,  and  of  the  oil-shales,  from  aquatic 
and  largely  cellular  plant  debris,  is  emphasized  very  properly  by  Mr. 
Hackford.  Putting  the  distinction  in  terms  related  to  the  chemical 
distinctions,  coals  may  be  said  to  be  characterized  by  ingredient  carbo- 
hydrates, while  oil-shales  embrace  waxy,  resinous,  gelatinous,  and  other 
plant  products. 

E.  DEGOLYER,  New  York,  N.  Y. — Since  it  had  always  been  held  that 
the  oil  found  in  the  coal  mines  of  England  was  distilled  from  the  coal,  it 
became  extremely  important  to  prove  whether  or  not  it  was  a  coal-tar 
distillate  or  true  petroleum.  This  was  Mr.  Hackford 's  contribution  to 
that  work. 

He  has  given  also  some  interesting  suggestions  as  to  the  origin  of 
Mexican  oils  and  the  Gulf  Coast  oils.  His  theory  provides  for  the  sulfur 
content  of  the  oils  of  coastal  Texas  and  Louisiana,  the  Isthmus  of  Te- 
huantepec  District  and  the  Tampico  District.  The  Tampico  area  is  not  a 
salt-dome  region,  but  its  oils  have  a  high  sulfur  content. 

I  have  not  paid  much  attention  to  oil-shales,  but  I  have  observed  that 
the  English  chemists  and  geologists,  who  are  best  acquainted  with  oil- 

*  Chief  Geologist,  Humble  Oil  &  Refin.  Co. 


224  NATURE   OF   COAL 

shales  and  not  so  well  acquainted  with  petroleum  as  their  American 
colleagues,  think  that  the  oil-shales  are  derived  from  petroleum;  the 
petroleum  came  first  and  the  oil-shales  as  some  sort  of  secondary  product. 
American  geologists  and  chemists  seem  to  argue  in  the  other  direction. 
We  are  better  acquainted  with  petroleum  than  with  the  oil-shales  and 
there  is  a  marked  tendency  at  present  to  regard  petroleum  as  resulting 
from  the  natural  distillation  of  oil-shales.  Both  groups  are  trying  to 
explain  the  known  by  the  unknown. 

REINHARDT  THIESSEN,*  Pittsburgh,  Pa.  (written  discussion f). — The 
writer  agrees  with  three  of  the  conclusions  drawn  from  investigations  of 
coal  by  means  of  solvent  extracts  and  low-temperature  distillation,  but 
does  not  fully  agree  with  the  conclusion  that  the  cellulosic  compounds  in 
coal  result  in  the  formation  of  phenols  upon  dry  distillation.  He  believes 
that  there  is  not  enough  proof  to  warrant  so  definite  a  conclusion.  Ex- 
perimental proof  does  not  indicate  that  phenols  result  entirely  or  ex- 
clusively from  the  cellulosic  derivatives  of  coal.  Only  relatively  small 
amounts  of  tar  are  formed  in  the  dry  distillation  of  cotton;  according  to 
Cross  and  Bevan,10  this  tar  is  composed  of  water,  furfurol,  phenols, 
liquid  and  solid  hydrocarbons;  according  to  Tollens11  it  also  contains 
allyl  alcohol  and  creosote.  Schwalbe'2  questions  whether  any  of  these 
products  are  formed  from  pure  cellulose;  he  believes  that  they  are  dis- 
tillation products  of  the  substances  associated  with  the  cellulose.  Why 
should  the  cellulosic  derivatives  in  coal  be  considered  the  source  of  the 
phenols  when  the  plants,  as  a  whole,  contain  so  much  and  so  many 
phenols? 

The  writer  has  given  considerable  time  to  the  study  of  the  origin  and 
constitution  of  coal  and  allied  substances  by  examining  thin  sections 
under  the  microscope  which  has  given  abundant  proof  that  the  important 
coal  beds  have  been  formed  from  woody  plants,  trees,  and  shrubs,  rather 
than  from  herbs,  grasses,  mosses,  and  algse  or  similar  organisms. 

The  mode  of  deposition  and  formation  of  the  peat  bogs  that  formed 
the  present  coal  seams  may  be  studied  by  examining  the  various  types  of 
existing  peat  deposits.  It  is  probable  that  each  kind  of  coal  seam  has  its 
analogous  deposit  in  present  deposits  of  peat.  For  example,  the  ordinary 
bituminous  and  subbituminous  coals  and  lignites  in  the  arboreal-peat 
swamps;  the  cannel  and  boghead  coals  in  the  quaking  bog  or  marsh;  and 
the  bituminous  or  oil-shales,  in  the  open  bog. 

A  study  of  arboreal-peat  deposits,  such  as  the  Dismal  Swamp  and 

*  Research  Chemist,  U.  S.  Bureau  of  Mines. 

t  Published  by  permission  of  the  Director,  U.  S.  Bureau  of  Mines. 

"  C.  F.  Cross,  E.  J.  Bevan,  C.  Beadle:  "Cellulose,"  69,  1895. 

11  B.  Tollens:  "Handbuch  der  Kohlenhydrate,"  1,  233,  1891. 

12  Carl  G.  Schwalbe:  "Die  Chemie  der  Cellulose,"  33,  1911. 


DISCUSSION  225 

those  found  abundantly  in  Wisconsin  and  Michigan,  shows  that  they  are 
composed  of  semi-decayed  logs,  branches,  twigs,  and  stems.  These  are 
embedded  in  a  general  debris  consisting  of  semi-decayed  chips  or  frag- 
ments of  wood  and  bark,  leaves,  cuticles,  rootlets,  small  twigs,  mosses, 
lichens,  in  all  degrees  of  fragmentation,  and  of  spores,  pollens  and  resins 
which,  in  turn,  are  embedded  in  an  attritus  derived  from  all  kinds  of 
plant  parts  and  the  whole  mass  has  been  transformed  into  peat  by  means 
of  putrefying  organisms.  The  resinous  contents  of  the  woody  parts  are 
still  in  place. 

There  is  only  a  relatively  short  step  from  peats  to  the  lignites.  A 
description  of  the  composition  and  the  constituents  of  peat  will  do  equal- 
ly well  for  that  of  lignite,  except  that  in  the  transformation  from  peat  into 
lignite,  coalification  process  has  taken  place  and  the  mass  has  been  greatly 
compressed  and  hardened. 

The  subbituminous  coals  are  formed  from  the  same  or  similar 
kind  of  plants  and  plant  products  laid  down  under  the  same  or  similar 
conditions,  and  often  during  the  same  time  as  the  lignites.  In  certain 
cases  a  lignite  bed  and  a  subbituminous  coal  bed  are  parts  of  the  same 
deposit,  but  the  transformation,  or  coalification,  has  gone  further  and  the 
mass  has  been  further  condensed  and  compressed  in  the  one  part  than 
in  the  other.  The  ordinary  bituminous  coals  form  but  another  step 
in  the  chain  of  the  transformation  of  peat  into  coal.  The  chemical 
nature  and  structure  must  necessarily  differ  widely  from  those  of  peat  or 
lignite  for  the  coalification  process  has  been  carried  on  for  a  longer  period. 

By  far  the  largest  part  of  coal  is  derived  from  logs,  stems,  branches, 
twigs,  and  roots,  which  are  represented  in  the  coal  by  the  black  glistening 
band  of  varying  thicknesses  and  widths.  The  thicker  and  wider  bands 
represent  logs  and  stems,  while  the  thinner  delicate  black  glistening 
bands  represent  smaller  chips  or  fragments.  The  duller  bands  between 
these  represent  the  general  debris,  which  consists  of  coalified  fragments  of 
all  kinds  of  woody  plant  parts  and  smaller  fragments  of  wood,  bark, 
leaves,  petioles,  cuticles,  and  macrospores,  and  an  attritus.  The  attritus 
consists  of  finely  macerated  coalified  plant  degradation  matter,  spores, 
pollens,  resins,  and  cuticles. 

The  bituminous  coals  are  generally  of  the  Paleozoic  age,  when  the 
.plants  were  chiefly  Calamites,  plants  belonging  to  our  modern  horsetails; 
Lepidodendrons,  and  Sigillarias,  plants  belonging  to  our  modern  club 
mosses  or  lycopods;  and  secondarily  of  Cycadophytes,  plants  belonging 
to  the  modern  Cycads;  Cordaites,  trees  belonging  to  the  recent  conifers 
and  ferns.  The  lignite-forming  plants  consisted  chiefly  of  conifers. 
This  difference  in  the  kind  of  plants  does  not  necessarily  account  for  the 
chemical  differences  since  the  chemistry  of  plants  is,  in  general,  quite 
the  same. 

The  cannel  and  boghead  coals  are  composed  largely  of  attritus, 

VOL.  LXV. 15. 


226  NATURE   OF   COAL 

which  consists  chiefly  of  spore  matter,  some  resinous  matter,  and  finely 
divided  plant  degradation  matter,  of  which  the  spore  matter  usually 
forms  by  far  the  largest  part;  they  usually  contain  a  large  amount  of 
inorganic  matter.  Anthraxylon  is  but  sparingly  present  in  the  boghead 
and  cannel  coals.  Beds  of  ordinary  coals  often  include  layers  that  are  in 
every  respect  like  cannel  coal.  When  such  layers  are  thick  enough  to  be 
easily  noticed,  they  are  called  bone  or  cannel  coal. 

The  oil-shales  are  in  many  respects  similar  to  the  cannel  coals;  the 
chief  difference  is  in  the  higher  mineral  contents  of  the  oil-shales.  Tor- 
banite  is  called  both  a  boghead  coal  and  a  rich  oil-shale;  before 
petroleum  was  discovered  it  was  extensively  distilled  for  oil. 

Oil-shale,  examined  with  the  microscope,  is  seen  to  contain  the  same 
kind  of  objects  as  cannel  coal  but  present  in  different  proportions.  In 
many  shales,  spore-exines  form  the  largest  part  of  the  organic  matter;  in 
others,  spore-exines  and  plant  degradation  matter  are  present  in  about 
equal  proportions;  in  some,  few  or  none  are  recognizable. 

As  deposits  that  contain  constituents  very  similar  to  those  contained 
in  oil-shales  are  being  laid  down  at  the  present  time,  much  may  be  learned 
through  their  study.  Such  deposits  are  being  laid  down  in  depressions 
without  proper  drainage  containing  a  rather  shallow  body  of  water. 
The  water  is  not  deep  enough  to  prevent  vegetable  growth,  but  it  is  too 
deep  for  a  woody  plant  growth,  consequently  a  luxurious  aquatic  plant 
and  animal  life  is  sustained.  As  long  as  this  area  is  maintained,  the 
dead  plant  and  animal  matter  largely  decays  and  disintegrates.  Certain 
parts  of  the  plants  and  certain  plant  products,  though,  resist  decay; 
pollen  grains,  spores,  resinous  matter,  waxes,  cuticles,  certain  woody 
parts,  etc.,  are  among  these.  But  even  in  the  decay  of  the  more  delicate 
parts  a  resistant  degradation  matter  is  left.  All  of  these,  together  with 
the  mineral  matter  of  the  plants  and  that  blown  into  it  as  dust  and  washed 
into  it  by  streams,  form  a  slimy  ooze  at  the  bottom,  which  on  drying  has 
much  the  appearance  and  consistency  of  art  gum.  In  many  respects 
it  is  similar  to  peat.  The  constituents  are  of  the  same  kind  as  those  of 
the  oil-shales. 

Plants  consist  mostly  of  cellulose  and  its  modified  form  known  as 
lignocellulose;  unfortunately,  too  little  of  the  chemistry  of  this  substance 
formed  through  decay  is  known.  After  wood  has  partly  decayed,  as 
the  wood  in  peat,  it  is  no  longer  cellulose  nor  lignocellulose;  nobody  knows 
what  it  is.  In  addition  to  lignocellulose,  plants  contain  resins,  gums, 
waxes,  fats,  oils,  tannin,  proteins,  chloroplasts,  various  kinds  of  alcohols, 
ketones,  aldehydes,  acids  of  the  aliphatic  series;  and  phenols,  quinones, 
alcohols,  aldehydes,  ketones,  acids,  turpenes,  camphors,  glucosides,  tan- 
nins, alkaloids,  and  others  of  the  aromatic  series.  Many  of  these  are  stable 
compounds  and  resist  decay;  others  have  resistant  radicles  and,  after  the 
end  products  or  side  chains  have  been  torn  away  through  putrefying  and 


DISCUSSION  227 

coal-forming  agencies,  leave  a  resistant  substance.  Particularly  significant 
in  this  respect  are  the  heterocyclic  and  the  cyclic  plant  compounds  and 
their  derivatives.  All  organic  plant  substances  are  organic,  or  carbon, 
compounds  either  in  a  straight  carbon  chain,  a  carbon  ring  or  rings  with 
side  chains  or  end  groups,  and  all  are  capable  of  losing  their  side  chains  or 
end  groups  and  leaving  a  hydrocarbon  compound.  During  the  trans- 
formation of  plant  substances  into  coal,  cannel  coal,  or  oil-shale,  there  is  a 
reduction  reaction  and  the  organic  compounds  tend  to  form  hydro- 
carbons ;  geologists  term  this  deoxygenation.  This  process  also  constitutes 
what  is  generally  termed  bituminization.  But  we  have  no  clear  idea  of 
what  bituminization  is  nor  what  constitutes  a  bitumen. 

We  have  some  knowledge  as  to  what  is  going  on  in  the  transformation 
of  the  plant  substance  into  peat.  Many  of  the  organisms  bringing  about 
fermentation  and  putrefaction  have  been  isolated  and  their  activities 
studied  and  their  products  have  been  analyzed  and  are  known.  But 
after  the  deposits  have  been  covered  for  years,  and  the  activities  of  the 
organisms  have  ceased,  changes  continue.  What  these  changes  are  and 
how  they  are  brought  about  should  be  a  fruitful  field  for  research. 

C.  E.  WATERS,*  Washington,  D.  C.  (written  discussion). — The  paper 
is  of  interest  because  of  its  bearing  on  the  behavior  of  petroleum  oils  when 
used  as  lubricants  in  internal-combustion  engines.  Up  to  90°  or  100°  C., 
petroleum  oxidizes  very  slowly  in  the  dark;  at  200°  C.  and  above,  the  oxi- 
dation may  be  very  rapid,  with  the  formation  of  compounds  that  are  pre- 
cipitable  by  the  addition  of  petroleum  ether.  "Sludging"  tests  for  trans- 
former oils,  Kissling's  tar-  and  coke-forming  tests,  and  the  writer's 
"carbonization"  test  are  based  on  this  fact. 

The  rate  of  oxidation  is  accelerated  by  increasing  temperature  and  by 
the  presence  of  alkalies,  iron  oxide,  sulfur  and  sulfur  compounds,  and  the 
oxidation  products.  Filtration  through  bone  black  or  fuller's  earth 
largely  removes  these  oxidation  products,  which  are  in  solution,  or  per- 
haps more  correctly  in  colloidal  suspension,  in  the  oil. 

The  precipitates  thrown  down  by  petroleum  ether  are  almost  com- 
pletely soluble  in  benzene.  They  are  usually  dark  brown  and  fine  grained , 
so  that  they  form  porous  lumps  after  the  oil  is  washed  out  and  they  are 
dried  in  an  air  bath.  Some  of  the  precipitates  are  granular  and  some, 
after  drying,  are  jet  black  with  a  coaly  luster  and  look  as  if  they  had  been 
fused,  or  at  least  sintered  together,  during  the  drying. 

Some  chemists  reject  the  idea  that  the  carbon  deposits  in  an  engine 
can  be  formed  by  partial  oxidation  of  the  oil,  with  formation  of  asphaltic 
matter.  They  regard  cracking  and  incomplete  combustion,  both  of  which 
reactions  deposit  carbon,  as  the  causes.  But  these  deposits,  after  the 
removal  of  the  adhering  oil  by  extraction  with  petroleum  ether,  contain 

*  Chemist,  Bureau  of  Standards. 


228  NATUJRE    OF   COAL 

much  soluble  matter.  Benzene  extracts  several  per  cent.  Following 
this  pyridine  gives  a  dark-brown  solution  that  filters  easily.  Five  per 
cent,  caustic  soda  yields  a  dark-brown  solution  that  is  difficult  to  filter, 
evidently  on  account  of  its  colloidal  nature.  When  the  residue  on  the 
filter  is  washed,  enough  runs  through  to  render  the  filtrate  turbid.  The- 
addition  of  sodium  chloride  makes  caustic-soda  solution  easier  to  filter 
because  the  colloids  are  partly  precipitated,  as  is  shown  by  the  lighter 
color  of  the  solution. 


VALUE    OF   AMERICAN   OIL-SHALES  229 


Value  of  American  Oil-shales* 

BY  CHARLES  BASKERVILLE,  f  PH.  D.,  F.  C.  S.,  NEW  YORK,  N.  Y. 
(Chicago  Meeting,  September,  1919) 

SHALES  containing  "kerogen,"  or  bituminous  matter,  which  on  destruc- 
tive distillation  yield  oily  and  tarry  matters  resembling  petroleum  are 
here  designated  as  oil-shales.  They  differ  from  oil-bearing  shales  from 
which  petroleum  may  be  obtained  by  so-called  mechanical  means.  The 
educts  obtained  by  the  destructive  distillation  resemble  some  or  all  the 
varieties  of  petroleum,  depending  on  the  character  of  the  shale  and 
the  mode  of  treatment.  Some  shale  oils  have  a  paraffin  base,  some 
an  asphaltic  base,  or  a  combination;  some  run  high  in  sulfur  compounds. 
The  methods  of  refining  and  cracking,  therefore,  are  essentially  the  same 
as  are  used  in  refining  petroleums. 

In  1860,  in  this  country,  over  fifty  companies  were  successfully  dis- 
tilling various  natural  bituminous  materials  for  the  production  of  "  coal 
oil,"  used  for  illuminating  purposes.  The  discovery  of  petroleum  and  the 
failure  of  these  companies  to  save  and  utilize  the  valuable  byproduct, 
ammonia,  brought  about  their  inevitable  doom.  Prior  to  that  time, 
more  or  less  successful  efforts  were  made  to  produce  from  the  shales 
of  Scotland  oils  for  illuminating  and  heating  purposes.  Competition  of 
native  petroleum  from  the  United  States  early  eliminated  some  of  these 
companies  and  with  the  entrance  of  oil  from  the  Russian  and  other  fields 
into  the  world's  markets,  the  Scottish  oil-shale  industry  underwent 
serious  and  trying  experiences  until,  in  1916,  only  four  (Scottish)  were 
paying  concerns.  These  survived  only  through  energy  and  the  appli- 
cation of  skill  in  saving  valuable  byproducts. 

A  few  companies  have  successfully  operated  in  France  and  New 
Zealand.  The  Canadian  Government  showed  active  interest  in  the  New 
Brunswick  shales,  which  exist  in  quantity  and  are  more  valuable  than  the 
Scottish  shales.  The  retarded  development  of  that  valuable  asset  of 
the  Province  of  New  Brunswick  was  most  unfortunate,  especially  when 
the  product  was  so  much  needed  in  the  prosecution  of  the  war. 

The  economic  success  of  a  shale-oil  industry  depends  on  the  follow- 
ing factors : 

*  This  paper  was  presented  by  request  at  the  Denver  meeting  of  the  Institute. 
Delay  in  its  publication  gave  the  author  an  opportunity  to  revise  that  part  which  had 
to  do  with  the  prosecution  of  the  war.  However,  the  fundamental  features  concern- 
ing the  economic  development  of  an  important  natural  resource  are  given  as  indicated 
in  the  original  communication. 

t  Professor  of  Chemistry  and  Director  of  the  Chemical  Laboratories,  College  of  the 
City  of  New  York. 


230  VALUE    OF   AMERICAN    OIL-SHALES 

1.  The  shale,  on  distillation,  must  yield  an  oil  simulating  petroleum 
in  character  and  composition.     The  distillation  is  carried  on  in  retorts 
variously  designed,  preferably  to  make  the  process  continuous.     Nor- 
mally the  shale,  in  pieces  of  suitable  size,  is  fed  into  a  retort  near  the  top  of 
which  the  shale  is  subjected  to  a  fairly  low  lateral  heat.     The  products 
of  distillation  thus  produced  are  swept  out  by  a  current  of  gas  produced 
below.    As  the  shale  passes  through  the  retort  it  is  subjected  to  a  more 
intense  heat,  which  brings  about  the  distillation  of  the  heavier  products. 
The  carbonized  residuum  then  comes  into  contact  with  regulated  blasts 
of  steam  (and  air),  which  generate  water  (or  producer)  gas.     This  gas 
passes  through  the  cooler  parts  of  the  retort  and  assists  in  sweeping  out 
the  products  evolved  at  the  lower  temperatures.     The  entire  gaseous 
product  passes  through  suitable  condensers  to  remove"  the  oils,  paraffin, 
tar,  etc.,  and  through  scrubbers  to  remove  the  ammonia;  and  the  residual 
gas  is  then  burned  in  annular  chambers  to  provide  the  lateral  heat  re- 
ferred to.     The  ash,  often  more  than  50  per  cent,  of  the  original  shale, 
is  automatically  removed  from  the  other  end  of  the  retort  by  various 
mechanical  devices,  somewhat  similar  to  the  Mond-Lymn  sealed  gas 
producer.     The  Scottish  practice  involves  four  retorts  in  a  unit,  which 
units  are  multiplied  into  banks.     A  unit,  four  retorts,  handles  about  10 
tons  of  shale  per  day  of  24  hr.     The  condensers  and  scrubbers  resemble 
those  of  ordinary  gas  (coal  and  water)  works.     In  other  words,  there  is 
no  great  necromancy  in  distilling  oil-shales  and  refining  them,  as  some 
might  have  one  suspect  or  believe. 

2.  The  shale  must  yield  oil  in  such  abundance  as  to  pay  the  costs  of 
mining  and  treatment,  or  the  character  of  the  oil  must  be  such  that  it  pos- 
sesses unusual  value;  for  example,  a  high  percentage  of  paraffin,  or  a 
notable  amount  of  ichthyol. 

3.  Since   the  last-mentioned  conditions  are  comparatively  rare  in 
the  oil-shale  industry,   a  valuable  byproduct  is  essential  to  carry  the 
burden  of  mining  and  treatment.     The  combined  nitrogen,  which  is 
largely  converted  into  ammonia  in  the  distillation,  has  been  the  salvation 
of  the  few  surviving  Scottish  companies  and  must  be  an  important  con- 
sideration in  any  shale-oil  industry  anywhere. 

4.  Assuming  adequate  oil  educts  (30  to  60  gal.  per  ton  of  shale  dis- 
tilled) and  a  supporting  ammonia  output,  the  oil  shale  must  be  in  ample 
quantity  and  so  situated  as  to  be  mined  in  the  cheapest  manner.     Ade- 
quate water  supply  is  essential  for  condensing  and  other  purposes  for  the 
crude-oil  works. 

5.  An  adequate  supply  of  sulfuric  acid  for  the  absorption  of  the  am- 
monia is  essential.     If  30  Ib.  of  ammonium  sulfate  were  obtained  per 
ton  of  shale,   it  would  call  for  some  25  Ib.  of  sulfuric  acid  per  ton  of 
shale  treated   (round  figures  are  used),  or  12,500  tons  of  92  per  cent, 
sulfuric  acid  for  every  million  tons  of  shale  treated.     A  50,000,000  bbl. 


CHARLES  BASKERVILLE  231 

annual  production  would  thus  call  for  625,000  tons  of  sulfuric  acid,  which  is 
no  mean  quantity.  An  annual  increase  of  over  800,000  tons  of  ammonium 
sulfate  from  such  an  operation  would  materially  affect  the  market  for 
that  substance.  However,  the  product  has  a  variety  of  valuable  uses, 
not  only  in  agriculture  and  chemical  manufacturing,  but  in  refrigeration. 

6.  As  observed,  the  character  of  the  shale  and  the  mode  of  distilla- 
tion determine  tfre  quality  of  oil  obtained.  Although  the  process  and 
its  products  are  simple  in  outline  much  unknown  along  these  lines  awaits 
investigation.  It  is  known,  however,  that  different  modes  of  treatment 
yield  crude  oils  of  entirely  different  composition.  Furthermore,  the 
field-test  methods  practiced,  while  giving  valuable  empirical  information 
as  to  the  character  of  the  shale  under  a  uniform  system,  fail  utterly  to 
tell  the  proper  procedure  to  be  followed  to  secure  the  best  values.  Labo- 
ratory methods  come  nearer  the  truth,  but  the  only  truly  accurate  way 
is  by  commercial  tests  in  full-sized  units. 

The  character  of  the  shale,  whether  caking  or  non-caking,  is  important 
in  determining  the  proper  mode  of  treatment.  For  the  present  we  may 
dismiss  consideration  of  the  "caking"  shales,  which  really  involve 
methods  for  treating  cannel  coals,  and  consider  only  the  non-caking; 
that  is,  the  "curly"  (massive)  and  "paper"  shales.  Curly  and  slicken- 
sided  shales  are  characteristic  in  Scotland;  these  and  paper  shales  are 
found  in  Canada.  The  paper  shale  appears  to  predominate  in  certain 
parts  of  the  United  States. 

Much  discussion  has  arisen  as  to  the  best  method  of  treating  the  shales 
found  in  very  large  quantities  in  Colorado,  Nevada,  Utah,  and  Wyom- 
ing.1 It  has  been  claimed  that  the  Scottish  practice  is  not  the  best  for 
our  American  shales.  To  be  sure,  a  successful  industry  in  one  environ- 
ment may  fail  when  transplanted,  but  experience  has  led  me  in.  a  new 
field  to  adopt  the  best  practice  of  a  given  environment  and  then  allow 
it  to  evolve  with  the  changed  conditions.  There  is  reason  to  believe  that 
this  procedure  will  be  pursued  by  the  Bureau  of  Mines,  which  is  expected 
shortly  to  erect  a  commercial  experimental  plant  in  the  field.  Initiative 
has  already  been  shown  by  some  companies,  whose  engineers,  as  a  result 
of  research,  have  erected  small  experimental  plants. 

Several  processes  have  been  devised  to  strip  the  oil  of  its  gasoline  as 
fast  as  it  is  produced.  Some  attempt  to  fractionate  even  further  (light 
oils,  fuel  oils,  and  residuum)  during  production;  this  line  of  attack  does 
not  commend  itself  to  me.  The  crude  oil,  stripped  of  gasoline,  will 
have  an  inferior  value  and  will  still  require  refining,  as  will  also  the  gaso- 
line thus  stripped.  One  of  the  most  noteworthy  processes  is  based  on 
a  circulation  of  gas,  which,  after  scrubbing,  passes  back  through  the 
distilling  mass,  thus  taking  advantage  of  the  vapor  pressure  of  the  dis- 

1  See  the  reports  of  the  Bureau  of  Mines  and  the  Geological  Survey  of  the  United 
States,  especially  Bull.  641-F  by  Winchester  (1916). 


232  VALUE    OF   AMERICAN   OIL-SHALES 

tillation.  The  distillation  is  thus  accomplished  at  a  much  lower  tempera- 
ture, with  a  saving  of  fuel  and  a  larger  yield  of  valuable  products. 

Whatever  process  may  be  proved  to  be  most  suitable,  and  no  doubt 
several  may  be  shown  to  possess  distinct  advantages,  it  must  be  re- 
membered that  the  production  of  shale-oil  in  the  West  is  not  so  much  a 
problem  of  mining  as  of  manufacturing.  Indications  point  to  the  easy 
application  of  the  simplest  mining  methods  to  this  field.  The  mining 
question  has  been  dealt  with  in  reports  by  Winchester,2  Hoskins,3  and 
others,  especially  George,4  whose  advice  in  regard  to  oil-shales  in  Colo- 
rado in  particular  should  be  sought. 

The  production  of  petroleum  in  the  United  States  is  not  keeping  pace 
with  consumption.  This  condition,  while  it  was  accentuated  by  the 
war,  is  not  an  actual  outgrowth  of  it.  The  extension  in  the  use  of  the 
gas  engine  and  the  development  of  oil-power  energy  producers  have 
caused  notable  increases  in  the  consumption  of  liquid  fuel.  The  rich 
Mexican  fields  may  supply  the  deficit  in  production  within  the  United 
States  and  the  untapped  oil  reservoirs  of  South  America  may  yet  flow 
to  our  refineries,  but  the  difficulties  of  transportation  and  the  establish- 
ment of  satisfactory  trade  relations,  which  are  not  unsurmountable,  im- 
press one  with  the  importance  of  self-containedness,  especially  in  con- 
nection with  a  raw  material  on  which  so  much  of  our  national  industry 
depends. 

The  annual  production  of  crude  petroleum  within  the  United  States 
for  1918  is  estimated  at  300,000,000  bbl.  This  will  require  a  material 
addition  to  keep  the  477  refineries  in  operation  up  to  their  capacity  of 
490,000,000  bbl.  annually.  Hence  new  oil  fields  or  new  sources  of  crude 
oil,  or  both,  must  be  developed.  Rumors  of  prospecting  in  some  new 
fields  and  of  active  attempts  to  open  up  new  pools  in  old  oil  regions  are 
current.  War  demands,  which  obtained  and  are  likely  to  continue  for 
some  time,  and  the  lack  of  a  universal  carburetter  inhibit  the  use  of  such 
substitutes  as  benzene  and  ethyl  (grain)  and  methyl  (wood)  alcohols 
for  the  time  being.  To  meet  the  deficiency,  within  recent  months  at- 
tention has  been  directed  acutely  to  the  enormous  latent  fuel-oil  resources 
dormant  in  American  oil-shales. 

Recently  my  attention  has  been  drawn  to  a  variety  of  flamboyant 
advertisements  in  connection  with  the  shale-oil  industry,  which  were 
so  misleading  that  I  hope  the  Institute  will  take  adequate  steps  to  safe- 
guard, as  well  as  foster,  a  promising  industry.  It  is  no  business  for  an 
individual  who  expects  quick  returns.  Too  much  stress  cannot  be  laid 
upon  the  fact  that  it  is  a  manufacturing  industry  requiring  ample  capital 
for  large  operations  with  the  very  best  of  technical  skill.  With  these  and 
with  patience,  the  enormous  resources  now  dormant  in  American  oil- 
shales  may  be  developed  into  a  great  and  profitable  industry. 

2  Op.  cU.  '  ^tate  Geologist  of  Colorado. 

*  Min.  &  Sci.  Pr.  (Apr.  13,  1918). 


DISCUSSION  233 

DISCUSSION 

ARTHUR  L.  PEARSE,  London,  Eng.  (written  discussion). — In  the 
last  paragraph  Professor  Baskerville  correctly  sums  up  an  important 
position.  The  paper  was  probably  written  some  months  ago,  as  is 
indicated;  if  it  were  written  today  he  would  have  further  emphasized 
these  conclusions.  The  oil-shale  is  a  great  industry,  has  been  for  many 
years,  and  bids  fair  to  become  one  of  the  most  important.  This  industry 
and  its  twin — the  carbonization  of  coal — are  the  most  important 
unorganized  industries  in  the  world  today. 

We  are  not  precise  enough  when  we  talk  about  the  Scotch  shale-oil 
practice.  If  reference  is  made  to  the  system  of  retorting  that  reached 
an  assumed  standard  some  10  yr.  ago,  I  would  say  that  no  one  would 
build  such  retorts  today;  but  they  are  good  enough  to  wear  out  and 
there  are  more  of  them  in  Scotland  than  there  is  shale  to  keep  them 
going.  If  the  reference  is  to  the  Scotch  system  of  treating  the  oil, 
evolved  out  of  much  experience  and  generally  adopted  as  standard  6  yr. 
ago,  I  would  say  that  this  method  has  been  replaced  by  fractional  dis- 
tillation and  cracking  plants.  The  old  Scotch  re  tor  b  is  not  the  best  to 
use  on  either  American  or  any  other  shale.  The  adoption  in  the  latest 
English  plant,  of  which  the  first  unit  is  1000  tons  daily,  of  an  entirely 
different  retort  proves  this. 

Principally  owing  to  better  practice,  evolved  out  of  work  on  the  car- 
bonization of  volatile  coals  and  other  hydrocarbons,  to  say  nothing  of 
shale,  we  have  learned  a  great  deal.  With  the  exception  of  the  cases  when 
the  carbonized  residue  is  required  in  such  shape  as  metallurgical  coke, 
for  instance,  and  for  which  the  coal  or  material  is  primarily  treated,  all 
the  older  methods  of  carbonization  in  ovens,  intermittent  or  continuous 
verticals,  etc.,  and  where  mass  carbonization  is  adopted,  are  obsolete. 
By  mass  carbonization  is  understood  the  heating  of  a  body  of  material, 
the  particles  of  which  are  in  close  contact  with  each  other,  in  contra- 
distinction to  a  condition  in  which  each  particle  is  unconfined.  Mass 
carbonization  involves  the  passage  of  the  heat  units  from  the  wall  of  the 
retort  into  the  center  or  through  the  charge;  as  this  action  proceeds,  it 
sets  up  the  best  heat  screen  with  the  corresponding  costly  results.  This 
is  why  the  consumption  of  heat  is  so  great  in  coke  ovens  or  vertical 
retorts.  The  act  of  carbonization  under  proper  conditions  is  almost 
instantaneous.  The  aim  of  modern  designers  is  to  approximate  this 
condition.  It  has  been  proved  that,  provided  the  gases  are  properly 
taken  care  of,  the  product  is  better  and  there  is  more  of  it.  Besides,  if 
gasoline,  or  motor  spirit,  is  a  desideratum,  the  faster  the  carbonization, 
the  better  the  spirit,  for  the  destruction  of  olefines  is  less,  especially  at 
low  and  similar  temperatures. 

It  must  not  be  forgotten  that  the  whole  tendency  of  destructive  dis- 
tillation, or  as  an  authority  has  recently  named  it,  "constructive"  dis- 


234  VALUE    OF   AMERICAN   OIL-SHALES 

tillation,  is  toward  lower  temperatures.  In  the  United  States  700°  F. 
is  used  by  one  plant  as  its  standard;  while  in  England  600°  F.  is  used 
with  the  best  of  results;  but  these  temperatures  necessitate  other  consid- 
erations if  a  reasonable  recovery  of  ammonia  is  required. 

The  adoption  of  the  principles  mentioned  have  resulted  in  low  first 
cost  per  ton-day  for  retorts  because  the  "through  put"  is  greater  owing 
to  better  heat  application.  The  amount  of  heat  used  is  one-third  less 
and  the  quality  of  the  product  is  better,  for  the  gases  are  withdrawn 
nearly  as  and  when  evolved. 

While  the  retort  has  been  the  most  serious  question  to  many,  the 
disposal  of  the  gases  has  also  been  troublesome,  especially  where  there  is 
a  shortage  of  water.  The  ponderous  and,  usually,  leaky  air  and  water 
condensers  formerly  so  universal  have  been  replaced,  even  in  Scotland, 
by  systems  of  fractional  condensation,  whereby  the  products  are  taken 
down  in  nearly  the  fraction  or  fractions  desired.  The  cost  of  this 
section  of  a  plant  is  practically  cut  in  half  and  so  is  the  trouble  and 
expense  of  running. 

A  big  through  put,  or  divisor,  is  essential  to  the  best  plants;  the  neces- 
sary capital  involved,  even  for  a  Scotch  plant,  was  enormous,  and  the 
plant  was  very  complicated.  Today  the  cost  of  a  modern  plant  can  be 
reduced  to  70  per  cent,  of  what  it  would  have  been  2  yr.  ago  and  at  least 
the  same  reduction  can  be  made  at  the  operating  end. 

Although  a  great  deal  has  been  done  toward  cheapening  and  simpli- 
fying the  process  of  carbonization,  Professor  Baskerville  is  right  when 
he  says  that  it  is  an  industry  requiring  capital  and  skill.  There  are 
many  angles  and  many  economic  conditions  to  be  considered;  not  the 
least  of  which  is  "  distribution. "  Notwithstanding  all  these,  it  may  now 
be  safely  assumed  that  it  is  quite  as  easy  to  distil  oil  from  shale  as  to 
drill  for  and  distil  oil  for  its  products,  and  on  the  whole  it  will  be  quite  as 
profitable  commercially. 

E.  A.  TRAGEB,  Bartlesville,  Okla. — I  have  distilled  something  over 
800  or  900  samples  of  western  oil  shales  and  find  that  it  is  possible  to 
get  different  products  by  different  types  of  distillation.  I  have  also 
found  that  by  the  same  method  of  treatment  the  shales  are  divided  into 
different  groups.  One  type  of  shale  tends  to  yield  gas  almost  entirely; 
the  majority  of  them  yield  mostly  oil;  while  there  are  some  that  give  a 
good  yield  of  both  gas  and  oil.  This  summer  I  found  a  type  that  by 
dry  distillation  will  yield  B.  S.  almost  entirely. 

THE  CHAIRMAN  (C.  W.  WASHBURNE,  New  York,  N.  Y.).— What 
conditions  do  you  find  give  the  best  results  in  distillation? 


DISCUSSION  235 

A.  W.  AMBROSE,  Washington,  D.  C. — The  matter  of  heat  control  is 
perhaps  one  of  the  biggest  factors  in  determining  the  quality  of  the 
different  byproducts. 

E.  A.  TRAGER. — You  can  produce  all  gas  and  no  oil  from  any  shale  by 
heating  too  rapidly,  but  as  near  as  it  is  possible  to  tell,  by  a  uniform 
method  of  distillation  the  different  shales  will  divide  themselves  into 
different  groups,  this  division  being  based  on  the  resultant  products. 

A.  W.  AMBROSE. — Did  you  try  any  experiments  by  grinding  shales  to 
different  sizes? 

E.  A.  TRAGER. — Yes;  but  the  size  does  not  seem  to  affect  the 
product.  We  tried  everything  from  J£  in.  to  Moo  in-  mesh  and 
the  product  is  very  much  the  same.  The  method  of  heating  is  the  im- 
portant factor. 

CHAIRMAN  WASHBURNE. — It  is  evident  that  this  matter  of  distil- 
lation of  oil  shales  is  something  for  our  grandchildren,  possibly  our  great- 
grandchildren, but  let  us  hope  that  scientists  will  begin  to  study  the 
problem  so  that  the  next  generation  may  have  some  good  out  of  it.  I 
believe  that  there  has  never  been  any  gasoline  or  kerosene  of  good  com- 
mercial quality  produced  from  our  Western  oil  shales  in  any  quantity. 
The  best  American  shale,  with  the  best  method  we  have,  would  take  too 
much  sulfuric  acid  in  treatment.  What  little  first-class  oil  would  be 
left  after  the  treatment  would  not  pay  for  the  cost  of  the  operations. 

E.  A.  TRACER. — I  found  some  oil  shales  that  yield  from  30  gal.  to 
60  gal.  per  ton,  which  on  distillation  will  yield  about  23  per  cent,  gasoline 
and  33  per  cent,  kerosene;  this  was  treated  with  H2SO4  and  the  loss 
wasn't  very  great.  The  samples  of  shale  which  contain  only  a  small 
amount  of  oil  yield  a  low  grade  of  oil;  while  at  the  same  time,  the  better 
shales  will  yield  more  oil  and  contain  a  larger  percentage  of  light  con- 
stituents. The  best  shales  which  have  been  found  to  date  come  from 
Colorado.  The  gasoline  is  apparently  of  very  good  grade  but  the  great 
objection  is  the  offensive  odor — it  is  very  undesirable — just  what  it  is,  I 
don't  know. 

CHAIRMAN  WASHBURNE. — Does  that  last  remark  apply  to  most  oil 
shales  in  Colorado  or  to  just  a  few  samples? 

E.  A.  TRAGER. — It  applies  to  all  Colorado  shales.  We  have  studied 
quite  a  number  of  samples  and  in  every  case  the  shale  that  yields  a  low 
amount  of  oil  will  yield  a  heavy  gravity  oil.  Some  of  the  crude  shale  oil 
is  quite  light;  the  first  of  the  yield  looks  somewhat  like  the  old  fashioned 
kerosene.  It  is  only  the  odor  you  will  have  to  contend  with. 


236  VALUE    OF  AMERICAN   OIL-SHALES 

R.  A.  SMITH,  Lansing,  Mich. — Mr.  H.  A.  Buehler  recently  told  me 
that  a  new  type  of  retort  for  coke  manufacture  has  been  developed  by 
G.  W.  Wallace  of  the  St.  Glair  County  Gas  Co.  of  East  St.  Louis,  111. 
This  retort  has  been  found  to  be  especially  adapted  to  oil  shales.  It  is 
entirely  different  from  the  standard  types  in  use  at  the  present  time. 
Coke  is  produced  in  4  hr.  and  the  treatment  of  oil  shales  is  completed  in 
about  the  same  time. 


INDUSTRIAL   REPRESENTATION  IN  THE  STANDARD  OIL  CO.    (N.  J.)       237 


Industrial  Representation  in  the  Standard  Oil  Co.  (N.  J.) 

CLARENCE  J.  HICKS,*  NEW  YORK,  N.  Y. 

(Lake  Superior  Meeting,  August,  1920) 

THE  labor  policy  of  the  Standard  Oil  Co.  (New  Jersey)  is  founded 
first  of  all  on  paying  at  least  the  prevailing  scale  of  wages  for  similar 
work  in  the  community;  on  the  eight-hour  day  at  the  refinery,  with 
time  and  one-half  for  overtime;  one  day's  rest  in  seven;  sanitary  and 
up-to-date  working  conditions;  just  treatment  assured  each  employee; 
opportunity  for  training  and  advancement;  payment  of  accident  benefits 
beyond  the  amount  prescribed  by  the  State  compensation  law;  health 
supervision  by  a  competent  medical  staff;  payment  of  sickness  benefits 
after  one  year's  service;  cooperation  with  employees  in  promoting  thrift 
and  better  social  and  housing  conditions;  and  assurance  of  a  generous 
annuity  at  the  age  of  65,  guaranteed  for  life  after  20  years  of  service. 
Most  of  these  features  have  been  a  part  of  the  company's  policy  for 
many  years,  but  it  is  only  during  the  past  two  years  that  the  cooperation 
of  employees  in  determining  these  matters  has  been  definitely  assured 
through  industrial  representation. 

Industrial  representation,  in  the  Standard  Oil  Co.  (N.  J.),  is  a  principle 
rather  than  a  procedure.  It  is  built  upon  the  belief  that  personal  as- 
sociation of  those  interested  in  any  problem  leads  to  a  mutual  under- 
standing and  a  fair  decision  as  to  what  is  right.  Fully  believing  in 
this  principle,  representatives  of  employees  and  representatives  of  manage- 
ment evolved  a  simple  plan,  the  basis  of  which  is  that  it  gives  every 
individual  employee  representation  at  joint  conferences  on  problems  and 
fundamental  principles  affecting  all  those  interested  in  the  industry. 
It  is  based  on  cooperation,  not  antagonism;  its  operation  makes  per- 
fectly clear  both  to  management  and  to  employees  that  their  interests 
are  identical,  and  not  at  variance  with  the  interests  of  the  stockholders, 
and  that  mutual  understanding  and  cooperation  insure  progress  and 
success  for  all.  Furthermore,  experience  has  definitely  shown  that 
representatives  of  the  employees  are  not  only  alert  for  the  employees' 
interests  but  are  as  keen  as  the  representatives  of  the  management 
in  determining  and  insisting  upon  fairness  to  the  employer. 

Though  the  plan  has  been  in  operation  nearly  two  years,  it  is  an 
experiment,  in  that,  being  based  on  a  principle  rather  than  on  cut-and- 

*  Executive  Assistant  to  the  President,  Standard  Oil  Co.  (N.  J.). 


238      INDUSTRIAL  REPRESENTATION  IN  THE  STANDARD  OIL  CO.   (N.  J.) 

dried  formulas  of  procedure,  it  is  still  subject  to  change  and  improvement 
It  has  proved  to  be  equally  applicable  in  a  refinery,  where  thousands 
of  men  are  assembled,  and  in  the  sales  department  and  the  producing 
field,  where  men  are  scattered  in  small  groups  over  a  wide  territory. 
It  is  also  in  operation  in  several  subsidiary  companies.  This  adjustment 
to  diverse  conditions  is  possible  because  hard-and-fast  rules  were  avoided, 
in  the  belief  that  the  human  element  must  play  an  important  part. 
Therefore  the  plan,  to  a  large  extent,  has  been  permitted  to  build  itself 
through  experience,  and  trial. 

The  plan  was  brought  into  operation  by  an  invitation  to  employees 
to  cooperate  in  maintaining  the  company's  established  policy  for  fair 
treatment  in  matters  pertaining  to  wages  and  working  conditions. 
This  invitation  outlined  a  simple  method  by  which  the  employees, 
by  secret  ballot,  might  elect  from  their  own  number  men  in  whom  they 
had  confidence  to  represent  them  in  conference  with  representatives 
of  the  management.  At  the  first  joint  conference  a  brief  plan  or  agree- 
ment was  evolved,  which  provided  that  adjustment  of  wages,  including 
matters  affecting  working  hours  and  working  conditions,  shall  be  made 
in  joint  conference  between  the  employees'  elected  representatives  in 
the  division  affected  and  the  representatives  of  the  company.  From 
the  beginning,  the  plan  stipulated  that  no  discrimination  shall  be  made 
by  the  company  or  its  employees  against  any  employee  on  account  of 
membership  or  non-membership  in  any  church,  society,  fraternity,  or 
union.  Agreement  was  made  as  to  offences  for  which  employees  may  be 
dismissed  without  notice  and  also  as  to  the  offences  for  which  an  employee 
should  be  warned  or  suspended.  Further,  each  employee  was  guaranteed 
recourse  against  unjust  treatment  or  unfair  conditions  by  means  of  a 
definitely  prescribed  method  through  which  he,  personally,  or  his  repre- 
sentative, may  appeal  his  case  to  joint  conferences  of  employees'  and 
management's  representatives  and,  if  necessary,  up  to  the  highest  officers 
of  the  company. 

The  joint  works  (or  plant)  conferences  are  held  at  regular  intervals 
to  consider  all  questions  relating  to  wages,  hours  of  employment,  work- 
ing conditions,  and  any  other  matters  of  mutual  interest  that  have  not 
been  satisfactorily  settled  in  the  joint  division  conferences.  These 
joint  division  conferences  meet  whenever  needed  to  discuss  and  adjust 
matters  within  the  smaller  confines  of  a  division.  Many  problems  never 
go  beyond  the  joint  conference,  unless  the  problem  develops  into  one 
that  concerns  other  divisions.  In  case  any  matters  were  to  come  up 
on  which  the  joint  works  conference  could  not  agree,  they  would  be 
referred  to  the  Board  of  Directors  for  final  decision.  But  as  yet  not  a 
single  case  has  been  referred  in  this  manner.  The  decisions  of  the  joint 
works  conference,  when  they  involve  serious  matters,  such  as  a  general 
increase  in  wages,  are  subject  to  the  approval  of  the  Board  of  Directors. 


DISCUSSION  239 

At  the  inception  of  the  plan,  a  basis  of  representation  was  determined 
upon  that  would  allow  one  employees'  representative  to  be  elected  by 
approximately  150  employees,  with  provision  for  a  minimum  of  two  em- 
ployees' representatives  from  each  division.  In  extending  the  plan  to 
other  departments  of  the  company,  such  as  the  producing  field  and  a 
refinery  where  fewer  employees  are  required,  this  basis  was  amended 
to  meet  the  conditions  obtaining  in  that  field.  On  this  point  two  es- 
sentials have  been  borne  in  mind:  First,  that  an  elected  representative 
must  not  have  more  constituents  than  he  can  easily  keep  in  touch  with ; 
second,  that  the  joint  conferences  must  not  be  so  large  as  to  be  unwieldy 
at  times  when  important  discussion  and  decisions  must  be  had.  Ex- 
perience has  shown  that  there  are  many  advantages  to  be  gained  by 
personal  contact  of  employees'  representatives  and  managements' 
representatives,  and  therefore  full  joint  conferences  are  preferable*  to 
numerous  smaller  subcommittees. 

Entirely  apart  from  the  industrial  representation  plan,  but  equally 
established  as  a  policy  in  the  Standard  Oil  Co.  (N.  J.),  is  a  method  of 
protection  for  employees  and  their  families.  This  is  attained  in  several 
ways:  Group  life  insurance  covering,  at  the  company's  expense,  every 
employee  after  one  year's  service,  affords  some  financial  resources  to 
dependents  in  case  of  death  of  an  employee — a  provision  that  was  greatly 
appreciated  during  the  influenza  epidemic  of  1918-19.  There  is  a  fully 
equipped  and  competently  manned  medical  department  to  look  after  the 
health  of  all  employees;  and  there  is  provision  for  half  pay  during  a 
period  of  sickness.  An  annuity  plan  provides  for  employees  who  retire 
after  20  years  of  service  or  who  are  incapacitated  after  even  shorter 
service.  These  forms  of  financial  security  are  considered  by  the  company 
as  being  good  business  and  therefore  are  maintained  solely  by  the 
company's  funds,  not  by  either  voluntary  or  involuntary  assessments 
on  the  employees. 

The  company  is  committed  to  a  policy  of  training  for  employees 
as  a  means  of  assuring,  to  each  one  who  desires,  an  opportunity  for  fair 
advancement  to  greater  responsibilities.  The  administration  of  training 
is  coordinated  with  other  personnel  functions,  such  as  selection  of  new 
employees,  transfers  and  promotions.  Thus  each  employee  not  only  has 
the  feeling  of  security  in  his  position  and  his  earnings  but  also  knows 
that  the  company  is  ready  to  help  fit  him  for  advancement  to  any  posi- 
tion within  his  capacity. 

DISCUSSION 

R.  A.  CoNKLiNG,*St.  Louis,  Mo. — After  three  months'  service  with 
our  company,  on  the  recommendation  of  the  head  of  the  department, 
any  employee  can  join  the  provident  fund;  then  a  fixed  percentage  of 

*  Head  Geologist,  Roxana  Petroleum  Corpn. 


240      INDUSTRIAL  REPRESENTATION  IN  THE  STANDARD  OIL  CO.   (N.  J.) 

his  salary  is  retained  and  deposited  with  the  parent  company,  with  a 
record  of  the  fund.  The  maximum  is  10  per  cent,  and  the  minimum  is 
5  per  cent.  The  company  sets  aside  an  equal  amount,  which  is  invested 
at  about  5  per  cent.  If  the  subsidiary  has  been  successful  during  the 
year,  the  company  declares  a  bonus  which  is  deposited  in  this  fund. 
For  the  last  three  years  the  bonus  was  15  per  cent.,  this  year  it  was  20  per 
cent.  That  makes  40  per  cent,  of  our  salaries  going  into  a  fund  into 
which  the  employee  only  pays  10  per  cent.  This  money  can  only  be 
drawn  out  after  three  years,  if  the  employee  leaves  the  company.  If  he 
leaves  the  company  before  that  time,  he  gets  only  his  10  per  cent. 

W.  E.  PRATT,*  Houston,  Tex. — A  point  worthy  of  note  is  that  this 
company  has  undertaken  to  insure  its  men  against  sickness,  to  pay 
reasonable  insurance  policies  in  case  of  death,  and  to  retire  the  men 
after  various  periods  of  service  on  livable  wages.  A  few  years  ago, 
although  we  heard  a  great  deal  about  sick  benefits  and  annuities,  most 
of  the  plans  called  upon  the  employees  to  contribute  something  from 
their  salaries,  but  at  the  present  time,  as  exemplified  by  the  policy  of 
this  corporation,  general  opinion  seems  to  hold  it  to  be  fairer  practice, 
as  well,  perhaps,  as  better  business,  to  supply  these  benefits  without 
placing  any  share  of  the  burden  involved  on  the  employee. 

*  Chief  Geologist,  Humble  Oil  &  Refin.  Co. 


PETROLIFEROUS  ROCKS  IN  SERRA  DA  BALIZA  241 


Petroliferous  Rocks  in  Serra  da  Baliza 

BY  EUZEBIO  P.  DE  OLIVEIBA,*  Rio  DE  JANERIO,  BRAZIL 

(Wilkes-Barre  Meeting,  September,  1921) 

ONE  of  a  recent  batch  of  samples  from  the  Serra  da  Baliza,  in  the 
state  of  Parand,  Brazil,  contained  asphalt  and  a  dark  heavy  oil;  and 
workmen  on  the  railway  from  Porto  Uniao  to  Uruguay  discovered  asphalt 
coming  from  eruptives  that  outcrop  along  the  Rio  de  Peixe.  The  occur- 
rence of  asphalt  in  the  triassic  eruptives  of  southern  Brazil,  however, 
has  been  known  a  long  time,  according  to  Dr.  Gonzaga  de  Campos. 

It  is  generally  believed  that  the  Botucatii  sandstone  is  always  a 
hard  vitrified  rock,  from  the  metamorphic  action  of  the  overflowing 
eruptive  contacts.  In  this  region,  however,  the  contact  met  amor  phism 
is  almost  nil;  the  sandstone  is  slightly  hardened  in  a  narrow  zone  about 
20  to  30  cm.  wide.  In  many  places,  the  sandstone  is  so  friable  as  to  be 
easily  reduced  to  sand,  which  is  used  in  mortar  for  building  in  Guara- 
puava  and  Palmas.  South  and  west  from  Porto  Uniao,  this  bench  of 
sandstone  is  about  50  m.  thick,  and  is  capped  by  a  heavy  bed  of  basic 
eruptives,  many  of  which  are  amygdaloids. 

NATURE  OP  ROCKS 

Dr.  Geo.  P.  Merrill,  after  studying  the  triassic  eruptives  collected  by 
the  Coal  Commission,  reached  the  conclusion  that  "All  these  rocks  are 
of  typical  basalt-diabases,  not  in  any  essential  different  other  than  in 
structure.  An  interesting  mineralogical  phase  is  its  paucity  in  olivine, 
which  in  many  cases  is  completely  lacking." 

Professor  Hussak,  who  carefully  studied  these  rocks  and  their  acces- 
sory minerals,  decided  that  in  the  dikes  they  are  granular  (diabase)  and 
that  in  the  lava  sheets,  porphyritic  (augite-porphyrite  or  melaphyre), 
and  that  the  latter  pass  evidently  to  normal  diabases  and  are  always 
typical  of  effusive  rocks.  The  examination  of  many  slides  from  dikes 
and  sheets  leads  us  to  adopt  the  opinion  of  Professor  Hussak;  the  rocks  of 
the  dikes  are  of  ophitic  structure,  while  that  of  the  sheets  show  a  great 
variety  of  structure  and  may  vary  from  almost  granular  to  basaltic. 
The  great  paucity  in  olivine  had  been  noted  by  Hussak,  who  classes 
as  melaphyres,  the  porphyritic  triassic  rocks  in  Brazil  which  contain 
olivine. 

*  Geologist,  Servigo  Geologico  e  Mineralogico  do  Brazil. 

VOL.  LXV. 16. 


242  PETROLIFEROUS  ROCKS  IN  SERRA  DA  BALIZA 

Between  Porto  Uniao  and  the  Serra  da  Baliza,  all  the  rocks, 
apparently,  are  in  sheets,  i.e.,  they  are  all  porphyritic,  containing  plagio- 
clase,  augite,  iron,  etc.  in  a  variable  proportion  as  well  as  the  many 
decomposition  products.  The  predominant  rock  is  black,  or  greenish 
black,  and  so  fine  grained  that  even  with  a  lens,  none  of  the  essential 
constituents  can  be  made  out;  it  contains,  however,  cavities  or  amygdules, 
empty  or  full  of  various  accessory  minerals,  products  of  its  decomposition. 
Another  rock  type  is  chocolate  colored,  of  a  cavernous  structure,  con- 
taining many  geodes  full  of  accessory  minerals.  This  rock  is  intercalated 
in  a  black  porphyry,  in  a  cut  in  the  Serra  da  Baliza.  In  a  cut  made  below 
the  humus  and  surface-earth,  rounded  blocks  of  decomposed  eruptives 
and  blocks  of  metamorphosed  sandstone  were  found,  and,  below  this,  the 
more  or  less  decomposed  eruptive  porphyry,  in  situ. 

The  Serra  da  Baliza  (1040  m.)  is  a  ridge  resulting  from  erosion  and  lies 
between  the  Rios  Jangada  and  Iratim  and  the  creeks  Antas  and  Janga- 
dinha.  From  a  geological  point  of  view,  it  is  constituted  essentially 
of  the  two  types  of  eruptives  noted,  with  the  metamorphosed  sandstone 
alongside. 

All  the  samples  of  sandstone  have,  when  freshly  broken,  a  distinct 
petroleum  odor  and  many  of  them  show  small  cavities  from  which  exude 
a  heavy  dark  oil.  Different  samples  of  the  compact  black  eruptive 
contained  asphalt  in  the  crevices;  while  the  chocolate-colored  rock 
showed  not  only  asphalt,  but  a  heavy  oil  that  came  out  with  effervescence 
when  heat  was  applied.  In  a  piece  of  quartz,  almost  hyaline,  a  cavity 
full  of  asphalt  was  found. 

Having  made  excavations  in  all  the  hollows  and  ravines  from  the  top 
of  the  Serra  to  the  foot  we  concluded  that  the  sandstone  does  not  form  a 
continuous  bed.  Probably  a  bed  was  broken  into  large  blocks  which 
were  carried  to  different  levels  in  the  molten  mass  during  the  eruptions 
of  the  porphyrites.  After  an  examination  of  a  part  of  these  rocks,  Dr. 
Gonzaga  de  Campos  decided  that  the  occurrence  of  petroleum  is  in  the 
contact  zone  of  both  the  sedimentary  rocks  and  the  eruptives  where 
these  are  completely  modified  by  endomorphism. 

INDICATIONS  OF  PETROLEUM  MOST  IMPORTANT  IN  BRAZIL 

These  indications  of  petroleum  in  the  Serra  da  Baliza  are  the  most 
important  known  in  Brazil.  Until  now,  the  greater  part  of  the  known 
occurrences  consisted  of  impregnations  in  clayey  and  calcareous  beds 
of  the  Iraty  shales  and  limestones  or  of  asphalt,  or  its  varieties,  at  different 
points  in  the  states  of  Sao  Paulo,  Parana",  and  Santa  Catharina.  Some 
rocks  above  the  Iraty  horizon  also  have  a  distinct  petroleum  odor  when 
freshly  broken.  One  such  occurrence  was  found  in  Sao  Paulo,  by  Dr. 
Gonzaga  de  Campos.  But  none  of  these  rocks  show  petroleum  immedi- 


EUZEBIO   P.    DE   OLIVEIRA  243 

ately,  when  freshly  broken,  as  do  those  of  the  Serra  da  Baliza.  Owing 
to  the  nature  of  the  rocks  of  the  region,  it  does  not  seem  wise  to  make 
borings  for  petroleum,  however,  until  more  minute  studies  have  been 
made. 

All  the  petroleum  indications  are  found  in  the  Iraty  beds  or  in  beds 
above  these.  As  far  as  known,  there  are  no  indications  of  oil  in  the 
underlying  Permian  rocks  nor  in  the  Devonian  beds,  except  a  slight 
impregnation  at  the  top  of  the  fossiliferous  shales  of  Ponta  Grossa. 

It  is  true  that  the  Bofete  well  log,  registered  in  Doctor  White's  report, 
mentions  an  oil  horizon  below  this  level;  but  it  is  quite  possible  that  the 
heavy  oil  given  as  coming  from  this  horizon  really  came  from  the  Iraty, 
the  rocks  of  which  show  oil  only  after  the  lapse  of  some  time  after  breaking 
or  boring — sometimes  this  occurs  only  after  the  application  of  heat. 

Near  the  Colonia  do  Rio  Claro,  the  existence  of  albertite  penetrating 
the  Estrada  Nova  and  Rio  Rasto  beds  has  been  known  some  years. 
This  occurs  near  an  eruptive  contact.  Albertite  seems  to  be  generally  a 
good  indication  of  petroleum,  as  shown  by  Doctor  White  in  the  same 
report:  "That  this  was  the  origin  of  grahamite,  albertite,  uintahite  or 
gilsonite  is  certain,  since  recent  drilling  near  the  Ritchie  mine  in  West 
Virginia  has  revealed  a  productive  oil  sand  (salt  sand)  at  1500  ft.  below 
the  valley,  and  what  is  most  significant  is  the  fact  that  only  a  little  oil  is 
found  in  the  underlying  sand  until  the  wells  are  located  from  500  to  800  ft. 
distant  from  the  fissure,  thus  showing  that  the  rock  has  been  drained  in 
the  immediate  vicinity  of  the  latter."  In  the  same  report,  he  says: 
"Record  of  a  well  drilled  within  300  ft.  of  the  Ritchie  mine  (fissure 
holding  grahamite),  on  the  Macfarlan  run.  In  this  well  only  a  small 
quantity  of  oil  was  found.  This  sand  was  good  but  the  well  acted  as 
though  the  sand  had  been  drained.  Wells  drilled  farther  from  the 
fissure,  however,  secured  good  producing  sand  as  shown  by  the  following 
records.  .  .  " 

Thus  drilling  for  oil  in  a  region  where  asphalt  occurs,  as  at  Colonia 
de  Rio  Claro,  is  promising  but  should  be  located  some  distance  from 
such  veins  of  albertite,  in  order  to  avoid  boring  through  rocks  from 
which  the  petroleum  has  been  drained. 

In  Sao  Paulo,  also,  other  borings  in  the  Bofete  region  would  be 
interesting.  Though  Horace  E.  Williams,  who  knows  the  region  well, 
is  of  the  opinion1  that  the  bituminous  sandstones  of  the  Bofete  region 
represents  a  fossil  pool,  eroded  and  oxidized,  and  that  the  existing  strata 
above  the  Iraty  in  that  immediate  region  are,  perhaps,  unfavorable  for 
such  accumulations.  Whether  or  not  this  is  true  can  only  be  determined 
by  considerable  drilling.  Corroborating  this  point  of  view,  in  part,  we 
find  in  the  Diario  Official  the  following  considerations  by  Doctor  White, 
written  while  he  was  on  the  ground:  "When  I  learned  that  the  boring 

1  Oil  Shales  and  Petroleum  Prospects  in  Brazil.     See  page  75. 


244  PETROLIFEROUS  ROCKS  IN  SERRA  DA  BALIZA 

near  Rio  Bonito,  in  Sao  Paulo,  had  found  some  genuine  petroleum,  I 
was  not  surprised;  but,  as  the  boring  had  been  made  near  a  fissure  in  the 
rocks,  which  permitted  a  great  quantity  of  the  petroleum  to  escape 
toward  the  surface  and  saturate  the  sandstone  with  its  residual  products 
(asphalt  etc.)  no  oil  might  reasonably  be  expected  to  be  found  in  com- 
mercial quantities  in  this  boring.  The  drilling  should  be  made  some 
distance  from  this  break  in  the  rocks  where  the  flow  of  eruptives  has 
not  emptied  the  deposits  of  the  underlying  rocks." 


ANALYSIS   OF   OIL-FIELD    WATER   PROBLEMS  245 


Analysis  of  Oil-field  Water  Problems* 

BY  A.  W.  AMBROSE,!  BARTLESVILLE,  OKLA. 
(St.  Louis  Meeting,  September,  1920) 

THE  underground  losses  of  oil  exceed  by  hundreds  of  thousands  of 
barrels  all  the  oil  that  has  been  lost  in  storage,  transportation,  or  refining. 
The  quantity  lost  is,  of  course,  indeterminate;  but  when  it  is  considered 
that  the  contents  of  an  entire  oil  field  have  been  excluded  from  recovery 
by  invading  waters,  some  idea  of  the  amount  wasted  may  be  gained. 
Similarly,  enormous  quantities  of  gas  have  been  lost  underground. 
Conservation  of  the  oil,  therefore,  should  start  before  it  is  brought  to  the 
surface  rather  than  after  it  is  placed  in  storage  tanks. 

Water  is  one  of  the  most  important  causes  for  underground  losses  and 
the  operator  should  give  as  serious  consideration  to  an  underground  flood 
of  water  as  he  would  to  a  destructive  surface  flood.  The  best  insurance, 
of  course,  is  to  have  the  wells  drilled  in  such  a  manner  that  water  has  no 
access  to  the  productive  oil  and  gas  horizons,  and  on  abandonment  the 
wells  should  be  properly  plugged. 

The  encroachment  of  edge  water  and  the  occurrence  of  waterin;the  base 
of  an  oil  sand  present  a  very  serious  problem  to  an  oil  company  sooner 
or  later  these  waters  are  bound  to  cause  considerable  damage,  if  they  do 
not  entirely  destroy  the  possibilities  of  further  production.  Too  often, 
however,  a  field  has  been  considered  to  be  in  a  hopeless  condition,  whereas 
wells  in  as  bad  a  condition  in  other  areas  have  been  repaired  and  the  life 
of  the  field  appreciably  lengthened.  The  corrections  are  very  often 
suggested  by  technical  study.  Very  successful  results  have  been  accom- 
plished by  detailed  underground  work  in  the  California  oil  fields,  in 
Gushing,  Oklahoma,  and  in  other  areas. 

The  purpose  of  this  paper  is  to  outline  briefly1  general  methods  of 
analyzing  oil-field  water  problems  in  a  producing  or  in  a  producing  and 
developing  oil  field,  with  a  view  to  suggesting  repair  work  on  offending 
wells.  Reference  is  continually  made  to  producing  oil  wells;  the  same 
general  method  of  procedure,  however,  should  be  adopted  in  a  gas  field. 


*  Published  by  permission  of  the  Director  of  the  U.  S.  Bureau  of  Mines. 

t  Superintendent,  Petroleum  Experiment  Station,  U.  S.  Bureau  of  Mines. 

1  A  bulletin,  "Underground  Conditions  in  Oil  Fields,"  prepared  by  the  writer, 
will  be  published  shortly  by  the  U.  S.  Bureau  of  Mines,  which  goes  into  much  more 
detail  than  this  outline. 


246 


ANALYSIS    OF   OIL-FIELD    WATER    PROBLEMS 


OBJECTIONS  TO  WATER  IN  PRODUCING  WELLS 

The  prime  necessity  of  mastering  the  underground-water  problem  is 
to  prevent  water  from  entrapping  the  major  portion  of  the  oil  still  under- 
ground. But  if  this  point  were  entirely  lost  sight  of,  there  are  sufficient 
reasons  for  studying  the  water  problems,  provided  the  study  is  followed 
by  corrective  measures. 

Water  is  objectionable  because  its  presence  in  an  appreciable  amount 
means:  (1)  The  ultimate  loss  of  thousands  of  barrels  of  oil  which  may 


7000 


6000 


1911     g     1912     g      1913     g     1914     g      1915 

FIG.  1. — EFFECT  OF  WATER  ON  OIL  PRODUCTION  OF  A  WELL. 

be  trapped  underground;  (2)  the  loss  of  casing-head  gas;  (3)  the  in- 
creased lifting  costs,  as  wells  producing  water  cost  more  to  pump  and 
the  life  of  the  tubing,  pump,  and  sucker  rods  is  shorter,  also  the 
additional  cost  for  replacement  of  corroded  pipe  lines  and  fittings;  (4) 
the  possibility  of  water  flooding  the  sands  and  driving  the  oil  to  neigh- 
boring property;  (5)  the  forming  of  emulsion,  which  necessitates  expen- 
sive dehydrating  plants  to  separate  the  oil  and  water. 

Fig.  1  shows  the  effect  of  water  on  oil  production  in  a  well.  Water 
appeared  in  this  well  in  January,  1912.  The  oil  production  held  up 
during  1912,  but  from  December,  1912,  to  May,  1913,  it  declined  from 
4800  to  500  bbl.  per  month.  Water  constantly  increased  during  1912, 
and  seriously  interfered  with  the  oil  production  during  the  first  part 
of  1913. 

DIFFERENT  WATERS  IN  A  WELL 

In  an  area  drilled  with  a  hole  full  of  mud  or  fluid,  the  operator  should 
consider  the  contents  of  a  sand  as  an  unknown  quantity,  unless  the 


A.    W.    AMBEOSE 


247 


sand  has  been  tested  in  a  neighboring  well  by  bailing  or  pumping.  In 
an  area  where  the  hole  is  filled  with  water  while  drilling,  the  hydro- 
static head  of  fluid  in  the  hole  is  usually  greater  than  that  of  the  water 
or  oil  in  the  sand,  hence  oil  or  water  will  not  come  from  the  sand  into  the 
drilling  well.  Fig.  2  is  a  hypothetical  sketch  showing  several  possible 
waters  in  a  producing  oil  field. 

Those  waters  A  and  AI  occurring  in  the  sand  above  the  producing 
oil  horizon  are  generally  known  as  top,  or  upper,  waters.  Top  water  may 
have  access  to  the  hole  by:  The  shut-off  being  too  high;  the  water  leaking 
around  the  shoe  of  the  water  string;  poor  coupling  connections,  due  to 


EJgeD1 


-Bottom 


FIG.  2. — HYPOTHETICAL  SKETCH  SHOWING  DIFPEEENT  WATER  SANDS 


cross-threading  or  the  pipe  not  being  screwed  tight;  collapsed  casing; 
a  split  in  the  casing;  pipe  worn  through  by  drilling-line  wear;  or  corrosion 
of  the  casing  due  to  strong  corrosive  waters  in  the  sands. 

Bottom  waters  E  are  those  occurring  in  sand  below  the  producing 
oil  horizons.  To  avoid  bottom  water,  it  is  necessary  to  learn  the  exact 
distance  between  the  top  of  the  water  sand  and  the  base  of  the  oil  zone, 
so  that  the  operator  can  avoid  drilling  too  deep. 

Where  there  are  several  producing  oil  or  gas  horizons,  the  water  C 
occurring  between  the  producing  sands  is  generally  referred  to  as  inter- 
mediate water.2 

Edge  water  D  occurs  in  the  down-slope  portion  of  an  oil  or  gas  stratum. 
Edge  water  may  be  middle  water  in  one  well  8  and  bottom  water  in  a 
well  in  another  part  of  the  field.  It  usually  encroaches  as  production  is 

2  If  there  are  only  two  producing  sands,  the  term  middle  water  is  often  applied 
to  the  water  occurring  in  a  sand  between  them. 


248  ANALYSIS   OF   OIL-FIELD    WATER   PROBLEMS 

drawn  from  the  wells  up  slope.  The  sand  is  termed  an  oil  producer  up 
slope,  but  wells  drilled  into  the  same  sand  down  slope  will  produce  water. 
Water  may  occur  in  the  base  of  an  oil  sand,  although  before  drawing 
such  conclusions  it  is  advisable  to  consider  carefully  whether  or  not  there 
is  a  small  formational  break  of  an  impervious  bed  between  the  oil  and 
water.  Water,  also,  may  occur  in  a  lenticular  body  of  sand  and  should 
be  treated  as  top,  bottom,  or  intermediate  water,  according  to  its  location 
with  respect  to  the  productive  sands. 

DATA  FOR  ANALYZING  OIL-FIELD  WATER  PROBLEMS 

The  following  outline  is  suggested  for  the  preparation  and  use  of  data 
in  the  study  of  water  problems  and  corrective  work  in  a  producing  field 
where  drilling  is  still  taking  place  and  where  little  or  no  data  have  been 
compiled. 

1.  Prepare  forms  for  recording  important  information. 

2.  Assemble  all  drilling  and  redrilling  records,  daily  well  reports, 
production  records  of  oil  and  water,  tubing  depths,  fluid  levels,  and  other 
data,  for  the  purpose  of  compiling  a  complete  log  for  each  individual  well. 

3.  Obtain  the  elevation  and  location  of  all  wells  and  prepare  field 
maps. 

4.  Present  underground  conditions  graphically  by  means  of  cross- 
sections,  underground  structure  contour  maps,  convergence  maps,  peg 
models,  stereograms,  and  miscellaneous  graphic  plots. 

5.  Study  data  on  drilling  and  behavior  of  neighboring  wells. 

6.  Collect   and   compile  individual   well  records  showing  monthly 
production  of  oil  and  water. 

7.  Review  the  histories  of  abandoned  wells. 

8.  Carry  on  certain  field  work,  such  as  collecting  samples  of  forma- 
tion, water,  and  oil  from  drilling  wells. 

9.  Conduct  field  tests  for  determining  the  contents  of  different  sands, 
also  test  out  "wet"  wells  for  top,  bottom,  intermediate,  and  edge  water 
and  water  in  the  base  of  an  oil  sand. 

10.  Study  the  chemical  properties  of  the  waters  in  different  sands. 

11.  Investigate  the  possibilities  of  using  dyes  or  other  detectors  to 
determine  the  source  of  the  water  in  wells. 

12.  Study  the  indications  of  a  field  going  to  water. 

13.  Consider  the  source  of  water  in  individual  wells  or  groups  of  wells. 

14.  Correct  or  repair  wells  making  water. 

Keeping  of  Records 

Records  form  the  basis  for  the  successful  operation  of  any  property 
and  may  be  considered  the  yardstick  by  which  the  past  and  present 


A.    W.    AMBROSE  249 

conditions  and  future  possibilities  may  be  measured.  Where  a  company 
has  no  complete  system  of  records,  immediate  attention  should  be  given 
the  preparation  of  forms  upon  which  to  record  important  data  and  to  the 
collection  of  information  for  these  forms.  The  forms  used  should  be 
those  necessary  to  keep  the  data  brought  out  in  the  following  pages. 

Well  Logs 

A  well  log  should  contain,  in  addition  to  the  formations,  location, 
and  elevation  of  the  well,  etc.,  a  history  giving  complete  data  of  the  tests 
and  all  work  done  on  the  well  that  will  in  any  way  serve  to  show  the 
contents  of  any  of  the  sands  or  the  condition  of  the  casing,  etc.  This 
history  should  be  arranged  in  a  chronological  form  in  which  each  piece 
of  work  is  set  out  by  itself. 

Field  Maps  and  Cross-sections 

Field  maps  should  be  prepared,  showing  the  elevation  and  location 
of  wells,  on  such  a  scale  that  the  wells  can  be  measured  or  scaled  off  as 
accurately  as  the  results  of  the  survey. 

Pins,  with  colored  glass  heads  or  with  numbers  on  the  head,  may  be 
stuck  into  certain  well  locations  to  serve  as  legends  to  designate  the 
status  of  different  wells.  A  certain  color  or  number  indicates  the  condi- 
tion of  the  well,  as  drilling,  redrilling,  abandoned,  etc. 

In  order  that  cross-sections  may  be  of  the  greatest  use,  they  should 
be  clear  and  simple  and  should  emphasize  the  important  features  and 
omit  the  unimportant.  The  occurrence  of  oil,  gas,  and  water  should  be 
emphasized  and  the  casing  depths  should  be  noted.  All  unnecessary 
figures,  as  depths  of  formations,3  should  be  omitted,  as  these  tend  to 
obscure  the  more  important  data. 

Considerable  care  should  be  exercised  in  the  adoption  of  symbols  to 
be  used  in  cross-sections,  as  symbols  avoid  much  lettering  and  furnish 
the  basis  for  easy  correlation  of  the  different  logs.  The  symbols  selected 
should  be  in  contrast  with  each  other,  easy  to  recognize  and  easy  to 
plot.  Once  a  satisfactory  set  is  adopted,  the  same  symbols  should  be 
used  throughout  the  work. 

The  lines  of  cross-section  selected  should  be  such  as  will  depict  the 
underground  structure.  Every  well  on  the  property  should  be  included 
in  some  cross-section,  as  one  well  may  furnish  a  key  to  the  situation. 
In  case  an  isolated  well  is  located  off  the  line  of  a  cross-section,  consider- 
able care  should  be  exercised  to  see  that  it  is  projected  to  the  line  of  section 
in  a  proper  manner. 

3  It  is  often  advisable  to  record  the  depths  of  the  more  important  formations,  as 
top  and  bottom  of  oil  sands,  markers,  etc.,  but  the  practice  of  arbitrarily  recording 
the  depths  of  formations  should  be  discouraged. 


250  ANALYSIS   OF   OIL-FIELD   WATER   PROBLEMS 

A  satisfactory  scale  for  plotting  cross-sections  has  proved  to  be  100 
ft.  to  the  inch;  this  allows  sufficient  detail  to  show  a  2-  or  3-ft.  change  in 
the  formation,  which  is  about  as  close  as  is  ordinarily  detected  by  the 
drill.  It  is  only  in  exceptional  cases  that  there  is  justification  for  a 
different  horizontal  and  vertical  scale,  because  where  the  two  scales  are 
different  the  actual  conditions  are  not  properly  shown. 

Correlation  is  based  on  an  identification  of  one  or  more  identical 
strata  in  the  logs  of  many  wells.  The  term  " marker"  or  "key  bed" 
has  been  applied  to  formations  that  are  constant  in  thickness  and  occur- 
rence over  large  areas  and  can  be  recognized  in  most  of  the  wells.  An 
ideal  marker  is  a  .formation  that  carries  from  well  to  well,  is  of  uniform 
thickness,  and  can  be  readily  recognized  by  its  color,  hardness,  or  tough- 
ness. From  the  cross-sections,  the  engineers  should  try  to  trace  the 
marker  from  one  well  to  another.  In  regions  where  there  is  no  marked 
variation  in  the  thickness  of  the  formation,  the  producing  sands  are 
usually  a  certain  distance  below  the  marker.  This  interval  will  serve  as 
a  guide  in  new  wells  to  indicate  at  what  depth  the  water  string  should  be 
landed  and  the  producing  horizons  will  be  encountered.  Similarly, 
bottom  water  and  other  features  should  be  noted  in  relation  to  this  marker 
Faults  and  unconformities  throw  the  beds  out  of  their  logical  place  and 
cause  mistaken  predictions.  Formations  may  thicken  or  thin,  causing 
irregularities  in  the  occurrence  of  different  beds. 

Where  few  wells  have  been  drilled,  the  surface  structure  may  offer 
helpful  suggestions  in  correlating  the  underground  beds,  as  frequently 
the  general  surface  dip  will  indicate  the  attitude  of  the  beds  underground. 
Unconformities  and  other  irregularities,  however,  may  cause  underground 
and  surface  formations  to  dip  at  different  angles,  but  until  this  has  been 
established  very  often  the  engineer  has  no  other  guide  at  the  start. 

Underground  Structure  Contour  Map 

The  underground  structure  contour  map  is  useful  for  showing  the 
attitude  of  beds  in  regions  of  low  folds  and  faults  of  small  throw.  The 
structure  is  shown  by  means  of  contour  lines,  which  are  used  to  connect 
points  of  equal  elevation  on  the  surface,  bottom,  or  other  definite  horizon 
of  a  key  bed  or  marker.  A  structure  contour  map  is  made  up,  there- 
fore, of  a  series  of  contour  lines  used  to  show  the  configuration  of  such  a 
bed.  A  contour  interval  is  the  vertical  distance  between  the  different 
points  of  elevation  as  represented  by  contour  lines.  The  accuracy  of  a 
contour  map  depends  largely  on  the  number  and  distributions  of  eleva- 
tions over  a  given  area,  also  on  the  accuracy  of  the  well  logs,  their  loca- 
tion, and  elevation.  The  universal  recognition  of  a  marker  or  key  bed 
in  an  area  is  also  a  factor.  The  main  function  of  the  structure  contour 
map  is  to  show  broad  structural  relationships  over  a  large  area  in  a  way 


A.    W.    AMBROSE  251 

that  usually  is  not  given  by  the  most  careful  study  of  geological  cross- 
sections;  it  is  also  used  in  selecting  well  locations,  in  the  prediction  of 
casing  depths,  well  depths,  etc. 

Convergence  Maps  and  Peg  Models 

Where  the  surface  and  underground  beds  are  not  parallel,  as  in  some 
fields,  a  convergence  map  is  necessary  to  take  account  of  the  convergence 
or  divergence  of  different  beds. 

Peg  models  are  used  extensively  in  the  California  oil  fields,  also  in 
the  Gulf  Coast,  for  showing  structural  conditions  underground.  These 
models  are  used  for  correlation,  for  the  determination  of  proper  water 
shut-off  points,  location  of  water,  gas  and  oil  sands,  and  for  bringing 
out  any  marked  irregularities  of  well  depths,  water  shut-off s,  etc. 

Stereograms  and  Miscellaneous  Graphic  Plots 

Stereograms  are  used  to  show  graphically,  and  in  three  dimensions, 
the  broad  general  relationships  underground.  They  have  been  used 
very  little  to  determine  casing  depths,  water  shut-off  s,  etc. 

Miscellaneous  graphic  plots  can  be  used  to  emphasize  certain  fea- 
tures. For  example,  if  considerable  material  has  been  left  in  the  hole, 
its  location  in  relation  to  the  producing  sands  may  be  shown  by  an 
individual  graphic  plot,  which  brings  out  in  consecutive  order  the  work 
done  on  the  well  at  different  times.  The  history  may  be  shown  on  the 
same  sheet;  then,  by  a  combination  of  the  graphic  drawing  and  the  written 
history,  the  engineer  may  more  easily  realize  the  tests  made  and  the 
work  done  on  the  well. 

After  the  marker  has  been  definitely  established  in  a  group  of  wells 
in  a  district,  a  set  of  graphic  logs  may  be  plotted  to  a  common  strati- 
graphic  datum.  The  marker  of  different  wells  is  plotted  on  a  horizontal 
line  and  then  the  correlation  should  be  along  the  horizontal,  consequently 
any  irregularities  of  well  depths,  water  shut-off  s,  tops  of  plugs,  etc.  are 
readily  noted. 

Study  of  Neighboring  Wells 

Neighboring  wells  should  be  carefully  studied,  for  they  may  furnish 
information  that  will  help  to  solve  the  problem.  Cross-sections,  par- 
ticularly of  adjoining  line  wells,  should  be  made,  and  the  casing  depths 
and  histories  of  these  wells  carefully  studied  in  order  to  obtain  the 
same  information  as  is  gathered  on  the  company  wells.  There  should 
be  a  complete  exchange  of  well  data  between  neighboring  companies, 
particularly  line  wells.  It  has  been  proved  many  times  that  the  exchange 
of  information  is  beneficial  to  both  sides. 


252  ANALYSIS   OF   OIL-FIELD   WATER   PROBLEMS 

Monthly  Individual  Well  Production  Records 

The  production  records  of  wells  should  be  compiled  in  convenient 
form  and  should  show  the  production  of  oil  and  water  for  each  month 
during  the  life  of  the  well.  If  there  are  no  records,  information  should 
be  collected  from  the  foremen  and  pumpers.  Information  so  recorded, 
however,  should  have  a  note  telling  the  source  of  the  information. 

Abandoned  Wells 

In  preparing  data  on  different  wells,  special  attention  should  be  given 
to  the  histories  of  abandoned  wells,  because  these  may  be  allowing  water 
to  enter  the  producing  sands.  Where  records  of  such  wells  are  not  avail- 
able, it  is  often  necessary  to  collect  information  from  drillers,  pumpers, 
etc.  Every  abandoned  well  should  be  properly  plugged. 

Collection  of  Samples  of  Formation,  Water,  and  Oil 

Samples  of  formation  from  different  horizons  should  be  collected 
from  the  drilling  wells.  These  samples  should  be  examined,  marked, 
and  saved  for  future  reference.  Glass  bottles  may  be  used  as  containers; 
they  should  be  labeled  to  show  the  well  number,  depth,  name  of  forma- 
tion, and  date  collected.  Samples  of  water  representative  of  that  in  a 
sand  should  be  collected,  even  though  there  may  be  no  need  for  a  chemical 
analysis  at  the  time.  Samples  of  showings  of  oil  from  any  unexpected 
horizon  should  be  collected  for  possible  analysis  or  need  later. 

Field  Tests 

A  series  of  field  tests  of  wells  making  water  and  of  drilling  wells  should 
be  carried  on  simultaneously  with  the  study  of  the  data.  The  water 
strings  of  oil  wells  making  water  may  be  tested,  bottom  of  wells  may  be 
plugged  where  bottom  water  is  suspected,  and  the  sands  of  a  drilling 
well  should  be  tested.  The  same  sand  need  not  be  tested  in  several 
wells  as  one  good  test  on  a  horizon  in  a  certain  area  will  often  suffice . 
The  necessity  for  knowing  the  results  of  former  tests  emphasizes  the 
value  of  good  records. 

The  location  of  oil  sands  and  water  sands  can  be  determined  most 
satisfactorily  in  a  drilling  well  because  it  is  possible  to  have  only  one  sand 
exposed.  The  number  of  sands  that  can  be  tested  in  a  drilling  well  are 
limited  only  by  the  practicability  and  expense  of  the  operation.  Once 
the  sand  is  cased  off,  it  is  usually  difficult  to  make  a  test  of  it.  After  a 
water  string  has  been  landed,  a  very  careful  test  should  be  made  by  drill- 
ing a  pocket  below  the  casing  shoe,  bailing  out  water  and  allowing  the 


A.    W.    AMBROSE  253 

hole  to  stand  at  least  6  hr.,  and  preferably  12  hr.,  to  see  if  any  water 
enters. 

In  testing  the  water  string  of  a  producing  well,  first  test  to  see  if  there 
is  a  leak  in  the  pipe.  If  the  casing  does  not  leak,  a  bridge  may  be  set  a 
few  feet  below  the  casing  and  a  test  made  to  see  if  the  water  is  coming 
around  the  casing  shoe. 

If  a  well  is  suspected  of  making  bottom  water,  the  bottom  of  the  well 
can  be  plugged  in  successive  stages,  with  cement,  until  some  definite 
information  is  gained  regarding  the  source  of  the  water.  Packers  and 
lead  plugs  have  also  been  used.  In  plugging  up  the  bottom  of  the  well 
to  test  for  bottom  water,  it  may  be  necessary  to  shoot  the  hole  if  there  is 
any  old  side-tracked  casing  which  may  serve  as  a  conductor  for  the  water 
to  work  up  into  the  well. 

A  bridge  may  be  used  to  test  out  where  desired.  If  a  sand  midway 
between  the  water  shut-off  point  and  the  bottom  of  the  well  is  suspected 
of  making  water,  a  bridge  can  be  set  in  the  sand  suspected  of  carrying 
water,  cement  dumped  in  to  fill  the  hole  several  feet  above  the  sand  and, 
after  the  cement  has  hardened,  a  bailing  or  pumping  test  made  to  deter- 
mine whether  or  not  the  bridge  has  shut  off  the  water.  Very  often  a 
bridge  saves  a  great  deal  of  needless  plugging.  Often  intermediate  water 
can  be  located  by  deepening  and  testing  successively  lower  sands  in  a 
drilling  well. 

Testing  for  water  in  the  base  of  an  oil  sand  is  similar  to  plugging  and 
testing  for  bottom  waters,  although  much  more  care  must  be  exercised. 
It  is  important  to  plug  the  wells  with  cement  in  successive  stages  in  order 
to  avoid  shutting  off  the  oil  production.  If,  after  plugging,  the  amount 
of  water  is  retarded  only  temporarily,  it  is  evident  there  is  water  in  the 
base  of  an  oil  sand. 

The  field  tests  for  edge  water  or  water  in  a  lenticular  sand  are  neces- 
sarily guided  by  the  suspected  location  of  the  water;  that  is,  whether  the 
water  occurs  in  the  top,  bottom,  or  intermediate  sands. 

Water  Analyses 

The  chemical  analyses  of  oil-field  waters  can  be  used  in  solving  oil- 
field water  problems.  They  are  particularly  useful  in  distinguishing 
waters  in  different  sands,  and  hence  in  determining  the  source  of  water 
in  a  "wet"  well.  Perhaps  the  most  practical  use  of  chemical  analyses 
has  been  in  the  oil  fields  of  the  Gulf  Coast  and  of  California,  where  their 
use  has  saved  costly  work  that  otherwise  would  have  been  necessary  to 
determine  the  source  of  the  water  in  some  of  the  wells. 

The  waters  of  each  field  are  chemically  different  from  those  of  another, 
and  the  engineer  will  find  that  the  distinguishing  features  of  different 
waters  will  probably  vary  in  each  field.  He  will  undoubtedly  find,  how- 


254  ANALYSIS   OF   OIL-FIELD   WATER   PROBLEMS 

ever,  some  particular  feature,  as  high  chloride  content,  total  solids,  or 
primary  salinity,  that  will  serve  to  identify  one  water  from  another. 
It  may  be  found  that  the  properties,  such  as  primary  salinity,  primary 
alkalinity,  etc.,  are  not  the  determining  characteristics  of  a  water  in 
a  field.  In  one  field,  the  writer  found  that  the  top  waters,  in  general, 
were  high  in  sulfates.  The  sulfate  content  decreased  as  the  sand 
approached  the  oil  zone;  and  as  the  chlorides  were  negligible  in  the 
top  waters,  there  was  a  decreasing  primary  salinity  percentage  with 
depth.  The  very  bottom  waters,  however,  had  a  high  chloride  content; 
hence  the  bottom  and  the  top  waters  would  have  high  salinity,  because 
primary  salinity  is  determined  by  adding  the  sulfate  (SO^  and  chloride 
(Cl)  percentages  together  and  multiplying  the  resulting  figure  by  2. 
The  operator  might  be  confused  if  he  relied  only  on  primary  salinity  to 
determine  the  characteristics  of  the  water. 

In  this  work,  the  writer  found  it  necessary  to  consider  the  chloride 
content  in  wells  before  giving  too  much  value  to  primary  salinity  percent- 
age. The  most  satisfactory  results  were  obtained  by  using  the  percent- 
age of  reacting  value  for  comparison  rather  than  the  figures  of  salinity 
and  alkalinity.  Again,  it  may  be  found  that  other  factors  will  readily 
distinguish  the  waters.  For  example,  the  bottom  water  of  the  Augusta 
field,  Kansas,  shows  total  solids  averaging  about  36,000  parts  per  million, 
while  the  upper  waters  average  nearly  four  or  five  times  as  much. 

Collection  of  Samples  of  Water  for  Analysis. — A  sample  of  water  for 
analysis  is  of  no  value  unless  it  is  representative  of  the  water  found  in  the 
sand.  The  samples  to  be  analyzed  should  not  be  mixed  with  drilling 
water  and  a  sample  is  of  little  value  where  several  water  sands  are  exposed 
in  the  hole.  When  starting  the  work,  the  engineer  should  collect  samples 
of  unmixed  waters  from  each  sand,  if  possible,  so  that  he  may  know  the 
properties  of  the  waters  in  definite  water  sands. 

Where  a  producing  well  has  made  water  for  some  time  a  true  sample 
may  be  obtained  from  the  flow  tank  or  sump,  as  other  water  has  been 
flushed  out.  If  the  well  has  just  started  to  make  water,  and  other  water 
has  been  in  the  tanks,  it  is  best  to  take  a  sample  from  the  lead  line. 

Application  of  Water  Analyses. — After  a  sample  is  collected  and  a 
chemical  analysis  made,  the  engineer  should  interpret  the  analysis 
according  to  Doctor  Palmer's  method.  When  there  are  several  analyses, 
a  tabulation  should  be  made  of  the  properties  of  the  waters  in  known 
sands  and  of  the  distances  of  these  sands  from  the  marker.  Then,  when 
a  well  starts  to  make  water,  its  source  can  be  determined  by  comparison 
of  the  chemical  properties  of  the  water  with  those  in  the  tabulation  to 
see  if  it  is  the  same  water  as  any  of  those  recorded  in  the  tabulation . 

To  show  the  possibilities  of  using  water  analyses,  the  writer  will  cite 
one  or  two  examples,  taken  from  a  report  of  the  waters  in  the  East  Side 
Field,  Coalinga,  Calif.,  by  the  writer  in  September,  1916,  to  Mr.  B.  H. 


A.    W.    AMBROSE 


255 


van  der  Linden,  field  manager  of  the  Shell  Company  of  California.  It 
was  based  upon  forty  samples  of  water  taken  from  sands  of  different 
wells,  the  samples  being  collected  from  as  many  different  sands  as  were 
accessible.  By  studying  the  analyses  in  connection  with  the  graphic 
sections  and  well  histories,  it  was  possible  to  locate  very  definitely  most 
of  the  water  sands  associated  with  production.  The  results  of  this  work 
show  how  water  sands  may  be  definitely  located;  a  prime  necessity  to 
avoid  drilling  difficulties  and  future  water  troubles.  Table  1  demon- 
strates how  it  was  possible  to  distinguish  between  the  different  waters 
by  reference  to  the  sulfate  (S04)  and  carbonate  (CO8)  columns. 

TABLE  1. — Characteristics  of  Water  Sands,  Arranged  in  Stratigraphic 

Sequence 


Well 

Source  of 
Water,  in 
Feet  below 
Marker 

Na, 
Per 
Cent. 

Ca, 

Per 

Cent. 

Mg, 
Per 
Cent. 

S04 

Per 
Cent. 

Cl, 
Per 
Cent. 

C03, 

Per 
Cent. 

3, 
Per 
Cent. 

Record  5  

Above 

47 

1 

2 

39 

2 

9 

o 

Shell  31/34,  sample  No.  1.  . 
Shell  31/34,  sample  No.  2.  . 
Shell  31/34,  sample  No.  3.  . 
Shell  10/2 

355-365 
416-418 
420-438 
705-724 

48 
46 

49 
48 

2 
2 
1 

1 

0 
2 
0 
1 

28 
8 
1 

2 

10 
6 

5 

17 

12 
24 
29 
31 

0 

11 

14 

o 

The  water  from  Record  5,  which  is  above  the  tar  sand  and  producing 
sands,  has  39  per  cent,  sulfates  and  9  per  cent,  carbonates.  The  sulfates 
decrease  in  the  successive  lower  water  sands  to  Shell  31/34  No.  3  while 
the  carbonates  increase.  This  particular  sand  in  Shell  31/34  No.  3 
lies  just  above  the  producing  sands  but  below  the  tar  sands  of  that  well. 
The  sand  of  Shell  10/2  lies  below  the  producing  oil  zones,  the  top  of  which 
is  267  ft.  (81  m.)  lower,  stratigraphically,  than  the  bottom  of  the  water 
sand  in  Shell  31/34  No.  3.  This  bottom  water  is  low  in  sulfates  and  high 
in  carbonates,  as  would  be  expected  in  a  bottom  water  in  this  field, 
but  there  is  a  chloride  content  of  17  per  cent. 

Another  example  of  the  practical  application  of  water  analyses  to 
producing  wells  is  shown  in  Fig.  3.  This  well  was  drilled  to  2677  ft. 
(816  m.).  All  sands  were  perforated  and  the  well  put  to  pumping.  The 
well  produced  for  seven  days,  yielding  an  average  of  83  bbl.  of  oil 
and  104  bbl.  of  water  per  day.  It  was  expected  to  produce  oil  and 
no  water,  as  the  other  wells  in  this  area  were  producing  from  the  same 
horizons  and  making  no  water.  The  water  would  have  been  much 
more  with  a  larger  pump,  but  the2j^-in.  (6.4.-cm.)  pump  would  not  han- 
dle over  200  bbl.  of  fluid  per  day.  If  the  water  had  not  been  shut  off 
it  would  have  worked  back  into  the  oil  sands  and  probably  would  have 
done  great  damage. 

A  chemical  analysis  of  the  water  showed  it  to  be  a  decided  bottom 


256 


ANALYSIS    OF   OIL-FIELD    WATER   PROBLEMS 


water  as  the  sulfate  content  was  0.1  per  cent.,  the  chloride  content 
24.4  per  cent.,  and  the  carbonate  content  25.5  per  cent.  The  bottom 
waters  in  this  area  were  high  in  carbonates  and  chlorides  and  low  in 
sulfates.  Accordingly,  the  very  bottom  sand  was  plugged  off  by  ripping 
the  casing  and  filling  the  hole  with  cement  up  to  the  base  of  the  next 
sand — 2620  ft.  (798  m.).  The  cement  was  allowed  to  set  eight  days 
and  the  well  again  put  to  producing.  The  well  then  made  80  bbl.  of  oil 
per  day  and  1  bbl.  of  water. 


0.8. 

O.  S. 

O.S.-Sea  Shells 


BE! ORE  PLUGGING 


Shale -Sea  Shells 
Coarse 
Fine  Hard 
Sea  Shells 

Sdy. 


AFTEE  PLUGGING 
Total  Fluid 


7  Days 


Jiin  Eipptd  and  plugged 
to  2620ft  with  cement 
•WATER  ANALYSES 


SO4  ____  1 
CL---24.4 
C03._26,5 

FIG.  3.  —  PRODUCTION  OP  OIL    WELL   BEFORE  AND  AFTER  PLUGGING  OFF  BOTTOM 
WATER;  SOURCE  OF  WATER  WAS  DETERMINED  BY  CHEMICAL  ANALYSIS. 


Use  of  Detectors  for  Tracing  Movement  of  Underground  Waters 

Some  idea  of  the  rate  of  flow  of  water  from  one  well  to  another  may 
be  gained  by  the  use  of  dyes  or  other  flow  detectors.  Water  may  come 
into  a  well  from  various  sources  and  then  get  into  an  oil  sand  from  which 
other  wells  are  producing,  thereby  causing  considerable  damage.  In  an 
effort  to  trace  this  water  from  one  well  to  another,  severa  1  means  have 
been  used  and  others  suggested.  Certain  .flow  detectors  have  been  used 
with  a  fair  degree  of  success  in  some  oil  fields.  If  the  detector  placed 
in  one  well  appears  in  another  well,  it  shows  the  direction  and  rate  of 
travel  of  the  water;  but  where  the  detector  does  not  appear  nothing  is 
established.  The  best  organic  dyes  are  not  infallible,  primarily  because 
their  introduction  into  the  oil  sand  through  any  well  is  not  certain,  rather 
than  because  the  dye  may  be  destroyed  underground.  It  is  of  the 
greatest  importance  that  any  dye  or  detector  be  properly  introduced 


A.   W.   AMBROSE  257 

into  the  water  and  mechanical  means  for  insuring  this  can  probably  be 
developed. 

There  are  two  general  uses  of  dyes  or  other  flow  indicators  in  deter- 
mining the  movement  of  oil-field  waters:  To  determine  whether  or  not 
water  is  migrating  from  one  well  to  another;  and  to  determine  whether 
or  not  the  water  is  entering  the  well  through  a  leak  in  the  casing  or  around 
the  shoe  of  the  water  string. 

In  studying  water  migration  from  well  to  well,  the  dye  is  placed  near 
the  bottom  of  the  well  that  seems  to  be  flooding  the  other  well  or  wells, 
generally  in  solution  form,  by  means  of  a  proper  container  in  order  to 
prevent  dilution  of  the  dye  by  its  coming  in  contact  with  the  long  column 
of  fluid  in  the  hole.  Often  production  is  suspended  at  this  well  so  that 
the  dye  will  not  be  pumped  out.  Neighboring  wells  should  be  pumped 
vigorously  and  close  watch  made  of  the  water  for  any  evidence  of 
the  dye. 

Dyes  and  detectors  have  also  been  used  in  an  endeavor  to  find  out 
whether  or  not  the  water  string  is  leaking.  In  this  case  the  dye,  or  other 
material,  is  placed  on  the  outside  of  the  water  string  and  observations 
made  of  the  fluid  bailed  or  pumped  from  the  wells  to  see  whether  or  not 
the  dye  has  worked  its  way  into  the  well.  Its  appearance  in  the  water 
in  the  well  shows  the  existence  of  a  leak  in  the  water  string;  but  its  non- 
appearance  does  not  prove  the  effectiveness  of  the  shut-off,  for  if  the 
formation  has  caved  in  against  the  outside  of  the  pipe  a  few  hundred 
feet  below  the  surface,  the  dye  may  be  held  there. 

Methods  that  have  been  used  and  suggested  for  determining  the 
movement  of  underground  waters  are :  Dyes  and  other  materials  recog- 
nized by  their  color;  chlorides,  nitrates,  or  other  salts  recognized  by  chem- 
ical analyses;  lithium  salts,  which  can  be  detected  by  the  spectroscope; 
Slichter  electrical  method. 

Value  of  Dyes. — It  is  customary  for  the  operator  to  refer  to  fluorescein, 
eosine,  and  other  organic  dyes  as  " aniline  dyes"  although  some  of  them 
are  derived  from  substances  other  than  aniline.  Fluorescein,  eosine, 
methylene  blue,  magenta  or  fuchsine,  and  Congo  red  have  been  suggested 
as  dyes  which  could  be  used. 

Fluorescein  is  perhaps  the  best  organic  dye  that  can  be  used,  primarily 
because  it  is  noticeable  when  present  in  very  minute  quantities  and 
because  it  is  not  adsorbed  by  clays.  Fluorescein  will  penetrate  an  acid 
solution  further  than  eosine  and  will  give  a  color  reaction  that  eosine 
may  fail  to  do.  It  will  also  stand  sulfureted  hydrogen  and  sulfurous 
acid.  It  can  be  detected  with  the  naked  eye  when  present  in  the  pro- 
portion of  one  part  in  forty  million;  and  by  the  aid  of  the  fluoroscope  when 
present  in  the  proportion  of  from  one  part  in  five  hundred  million  to  one 
part  in  two  billion.  Congo  red  is  too  sparingly  soluble.  Methylene 
blue  and  magenta  are  basic  colors  and  all  basic  colors  are  adsorbed  by 

VOL.  LXV. 17. 


258  ANALYSIS   OF   OIL-FIELD    WATER   PROBLEMS 

clays  and  are,  therefore,  unreliable.  Fluorescein  and  eosine  are  not 
adsorbed  by  clays. 

Fluorescein  and  other  organic  dyes  have  been  used  with  success  in 
certain  cases  and  show  that  water  travels  from  one  well  to  another,  but 
so  far  as  the  writer  knows,  the  dye  has  failed,  in  the  majority  of  cases,  to 
appear  in  adjoining  wells  or  in  a  well  into  which  it  is  placed  when  it  was 
inserted  behind  the  pipe. 

Certain  inorganic  substances,  such  as  potassium  dichromate  and 
Venetian  red,  have  been  suggested  as  flow  detectors.  The  use  of  potas- 
sium dichromate  in  oil-field  waters  is  questionable,  however,  because 
many  oil-field  waters  have  a  yellowish  tint;  it  is  decolorized  by  reducing 
agents,  such  as  hydrogen  sulfide;  and  it  would  require  an  exceedingly 
large  amount  of  the  compound  to  color  such  a  large  volume  of  water. 
The  use  of  Venetian  red  also  is  limited  because  it  would  filter  out  quickly 
when  passing  through  a  sand;  furthermore,  it  is  not  detected  when  pres- 
ent in  as  small  quantities  as  is  fluorescein. 

Chlorides,  nitrates,  and  lithium  salts,  also,  have  been  suggested  as 
flow  detectors  but,  for  various  reasons,  their  use  is  limited. 

Slichter  Electrical  Method 

Slichter  has  described4  an  electrical  method  of  measuring  the  velocity 
and  direction  of  flow  of  underground  water  in  shallow  wells  (about  50  ft. 
in  depth) .  The  method  has  been  suggested  as  of  possible  use  in  detecting 
the  movement  of  underground  waters  in  oil  fields,  but  it  shows  no  promise 
of  practical  application  in  tracing  the  movement  of  underground  oil-field 
waters  in  deep  wells. 

INDICATIONS  OF  A  FIELD  GOING  TO  WATER 

The  flooding  of  the  oil  sands  of  an  area  by  top,  bottom,  or  intermediate 
water  can  often  be  prevented  by  the  correction  of  a  few  offending  wells 
when  the  trouble  starts.  The  operator  should,  therefore,  investigate 
promptly  any  marked  increase  in  the  water  content  of  a  well. 

The  indications  of  a  field  going  to  water  vary  with  each  locality,  but 
the  most  common  and  positive  evidence  is  for  the  oil  wells  to  start  produc- 
ing water.  When  a  group  of  wells  located  high  up  on  the  structure,  for 
instance  on  the  top  of  a  dome,  show  water  while  wells  down  slope  do  not, 
some  well  is  at  fault.  In  such  a  case  the  cause  may  be  due  to  improper 
water  shut-off  points,  leaky  water  strings,  wells  drilled  into  bottom  water, 

4  Charles  S.  Slichter:  Description  of  Underflow  Meter  Used  in  Measuring  the 
Velocity  and  Direction  of  Underground  Water.  U.  S.  Geol .  Survey  Water  Supply 
Paper  No.  110  (1905)  17-31;  or  Field  Measurements  of  the  Rate  of  Movement  of 
Underground  Waters.  U.  S.  Geol.  Survey  Water  Supply  Paper  No.  140  (1905). 


A.   W.   AMBROSE 


or  wells  improperly  plugged  when  abandoned.  Top  water,  bottom  water, 
and  water  in  a  lenticular  sand  may  show  in  wells  scattered  irregularly 
throughout  a  field;  these  three  waters  usually  lend  themselves  to  repair 
work  on  the  wells. 

Water  in  the  base  of  an  oil  sand  and  edge  water  present  a  much  more 
serious  problem,  for  as  the  oil  and  gas  are  withdrawn  they  will  be  replaced 
by  water.  Water  in  the  base  of  an  oil  sand  often  occurs  in  abundant 
quantities;  as  a  hole  is  carefully  plugged  up  with  cement,  and  by  stages, 
the  water  production  is  only  temporarily  retarded.  When  the  wells 
farthest  down  slope,  located  along  a  line  parallel  in  general  to  the  under- 


8CCO 


?iote:-UU  production 
increased  1940  bbl. 
per  month  just  pre- 
ceding and  foUovine 
i(pearai.ce  of  water 


1915 


FIG.  4. — INCREASE  IN  OIL  PRODUCTION  FROM  OIL  WELL  PRIOR  TO  ENCROACHMENT 

OF  EDGE  WATER. 

ground  contours,  show  an  increased  water  content,  there  is  suspicion  of 
of  the  encroachment  of  edge  water. 

A  sudden  increase  in  oil  production  has  been  noticed  in  wells  just 
before  edge  water  appears.  This  is  shown  in  Fig.  4.  It  will  be  noticed 
that  the  average  production  per  month  was  1940  bbl.  more  following  the 
appearance  of  water  in  appreciable  quantities  in  January,  1912. 


SOURCE  OF  WATER  IN  INDIVIDUAL  WELLS  OR  GROUPS  OF  WELLS 

Determination  of  the  source  of  water  in  a  field  is  dependent  on  accu- 
rate and  complete  records.  Each  well  presents  its  own  problem,  but 
there  are  certain  fundamentals  that  may  be  outlined  here.  Prob- 


260  ANALYSIS   OF   OIL-FIELD    WATER   PROBLEMS 

lems  should  be  attacked  from  two  sides — study  of  old  data  and  field  tests. 
As  the  problem  is  studied  from  the  records  and  graphic  data  prepared, 
the  suggestions  of  the  source  of  water  in  any  well  should  be  checked  and 
tested  by  mechanical  and  field  tests  on  the  wells. 

Production  records  indicate  the  wells  that  are  making  large  amounts 
of  water  and  complete  records  show  when  and  where  the  water  first 
appeared.  Fluid-level  records  may  possibly  indicate  what  well  is  causing 
trouble  afcd,  often,  water  analyses  will  show  immediately  the  source  of 
the  water.  The  history  of  an  abandoned  well  may  indicate  that  the  well 
was  not  properly  plugged,  hence  it  may  permit  water  to  flood  adjoining 
wells.  It  is  advisable  to  consider  whether  a  chemical  dye  has  been  used 
to  trace  the  water,  and,  if  so,  what  were  the  results?  Careful  consider- 
ation should  be  given  to  the  field  tests  made  on  the  different  water  strings. 

With  the  correlated  cross-sections  before  him,  the  engineer  can  make 
a  detailed  study  of  each  well  and  prepare  a  tabulation  showing:  (1)  The 
distance  between  the  marker  and  the  bottom  of  the  hole;  (2)  the  distance 
between  the  marker  and  the  bottom  of  the  water  string ;  (3)  the  distance 
between  the  marker  and  the  top  of  a  plug;  (4)  the  water  production  before 
and  after  the  plug  was  put  in;  (5)  the  water  production  before  and  after 
any  deepening  job;  (6)  the  initial  and  present  production  in  oil  and  water; 

(7)  date  at  which  the  well  started  to  make  a  serious  amount  of  water; 

(8)  remarks  as  to  what  any  field  tests  showed;  and  (9)  the  source  of  the 
water  according  to  the  analysis,  etc.    All  of  this  information  may  be 
tabulated  under  each  well  on  the  cross-section,  as  well  as  on  a  sheet  of 
paper,  where  there  are  many  wells  to  investigate. 

In  studying  histories,  it  may  be  noticed  that  water  appeared  at  a 
time  after  the  pipe  was  pulled  from  an  adjoining  well  which  was  improp- 
erly plugged  upon  abandonment. 

The  question  whether  or  not  a  well  is  making  top  water  should  be 
considered  from  two  phases:  First,  whether  the  water  string  leaks  and, 
second,  whether  the  casing  shoe  has  been  landed  too  high.  The  history 
will  also  indicate  whether  a  well  made  water  when  it  was  drilled  in  or 
whether  the  water  started  later.  The  history  will  also  show  what  bail- 
ing tests  were  made  on  the  wells  at  the  time  the  water  string  was 
landed.  If  the  original  tests  were  satisfactory,  the  chances  are  that 
water  has  not  broken  in  later. 

The  casing  may  be  tested  by  a  casing  tester  or  by  setting  a  plug  in 
the  casing  shoe;  again,  a  plug  may  be  placed  several  feet  below  the  casing 
shoe  of  the  water  string;  then  a  bailing  test  would  test  not  only  the  casing 
but  the  effectiveness  of  the  water  shut-off  job  as  well. 

In  looking  for  top  water,  the  engineer  should  first  select  a  well  at 
which  the  water  string  is  landed  highest  stratigraphically,  but  still 
makes  no  water.  After  the  proper  landing  point  for  the  water  shut-off 
strings  has  been  determined,  this  distance  should  be  expressed  with 


A.   W.   AMBROSE  261 

reference  to  the  marker,  so  that  by  the  use  of  sections  and  tabulations 
it  can  be  readily  told  whether  or  not  the  shut-off  point  is  too  high  in 
other  wells. 

The  possibilities  of  bottom  water  should  be  considered.  To  deter- 
mine if  the  well  has  been  drilled  too  deep,  as  indicated  by  the  tabulation, 
showing  the  safe  point  to  which  wells  may  be  drilled  without  encounter- 
ing bottom  water,  the  well  that  has  been  drilled  deepest  stratigraphically 
but  still  makes  no  water  should  be  selected.  This  then  determines  a 
depth  to  which  a  well  can  be  drilled  with  safety.  The  engineer  must 
bear  in  mind  that  often  comparison  can  not  be  made  of  wells  located  a 
great  distance  apart  because,  where  there  is  an  edge-water  condition, 
the  sand  down  slope  may  have  water  while  up  slope  it  contains  oil. 
Plugging  jobs  also  give  information  concerning  bottom  water.  If  the 
well  has  been  plugged,  the  engineer  should  review  the  tests  made  after 
any  plug  was  put  in  to  see  whether  or  not  there  is  good  evidence  that 
the  plug  was  tight.  If  bottom  water  is  suspected,  and  it  has  not  been 
plugged  off,  a  test  may  be  made  with  a  plug,  preferably  cement.  Bottom 
water  may  be  indicated  by  deepening  jobs  shown  in  the  history;  if  a 
well  made  no  water  until  deepened,  a  marked  increase  in  water  after- 
wards would  indicate  that  this  well  had  encountered  bottom  water. 
Bottom  waters  usually  have  distinct  chemical  properties. 

When  all  information  and  tests  indicate  that  it  is  not  bottom  water, 
the  possibility  of  water  coming  from  a  middle  horizon  should  be  con- 
sidered. This  is  a  difficult  water  to  test.  When  middle  water  is  pres- 
ent, it  is  necessary  to  make  certain  first  that  the  water  is  not  coming 
from  top  or  bottom.  If  the  water  string  is  landed  low  enough  and  the 
ori  inal  bailing  tests  indicate  a  tight  job,  and,  furthermore,  if  the  well  is 
not  drilled  deep  enough  for  bottom  water,  evidently  the  water  is  coming 
from  an  intermediate  source.  Evidence  is  also  gained  by  considering 
histories  of  adjacent  wells,  to  note  whether  these  wells  have  a  similar 
water  and,  if  so,  if  the  bottom  of  any  of  the  holes  has  been  plugged.  If 
a  plug  that  should  have  held  back  any  bottom  water  was  once  placed 
in  the  bottom  of  the  hole,  but  the  well  still  made  water,  there  is  indica- 
tion that  the  water  is  coming  from  higher  up  the  hole.  In  looking  for 
the  water  of  the  middle  horizon,  it  may  be  that  adjoining  wells  were 
deepened  in  successive  stages  and  the  histories  of  these  wells  may  in- 
dicate the  depth  below  the  marker  at  which  middle  water  is  encountered. 
The  middle-water  sand  often  has  definite  properties  distinct  from  those 
of  the  top  and  bottom  waters,  which  differences  are  brought  out  by  water 
analyses. 

Edge  water  may  be  suspected  when  a  group  of  wells  down  slope  show 
increased  oil  production.  In  addition,  a  group  of  wells  located  roughly 
parallel  to  a  structure  contour  may  show  a  sudden  increase  in  water. 
It  may  be  noticed  that  wells  will  produce  oil  from  a  certain  sand  in  one 


262  ANALYSIS   OF   OIL-FIELD   WATER   PROBLEMS 

locality  while  down  slope  this  same  sand  contains  water;  some  place 
between  these  wells  there  is  an  edge-water  line  and  in  time  the  water 
will  encroach  on  the  oil  wells. 

There  remains,  of  course,  the  possibility  of  the  wells  making  water 
from  the  base  of  an  oil  sand;  a  water  analysis  may  indicate  a  new  water 
which  lies  in  the  base  of  the  sand.  These  wells  usually  turn  from  oil 
to  water  very  suddenly.  Where  the  water  occurs  in  the  base  of  a  sand 
in  a  flowing  well  with  large  production,  there  is  little  evidence  of  gas  and 
the  well  often  flows  very  evenly.  The  production  of  water  coming  from 
the  base  of  an  oil  sand  is  only  temporarily  retarded  by  plugging. 

A  lens  of  water  will  be  detected  by  a  different  kind  of  water,  as  shown 
by  water  analyses;  a  study  of  well  histories  will  show  that  only  a  small 
number  of  wells  in  a  certain  locality  have  this  water.  Inasmuch  as  a 
lens  of  water  may  occur  in  any  part  of  the  geologic  column,  it  is  often 
referred  to  as  top,  bottom,  or  intermediate  water,  depending  on  its  loca- 
tion in  reference  to  the  oil  sands. 

CORRECTION  OF  WELLS  MAKING  WATER 

In  the  various  studies  and  field  tests,  the  engineer  should  have  ideas 
of  the  sources  of  water  in  the  different  wells  and  the  location  of  the  differ- 
ent oil  sands.  Recommendation  should  be  made  for  correction  of  wells 
that  may  be  letting  water  into  any  producing  oil  well. 

Top  Water 

In  case  of  a  leak  in  the  casing,  one  remedy  is  to  place  a  packer  between 
the  tubing  and  the  water  string.  Where  there  is  a  full  oil  string,  it  may 
be  necessary  to  cut  the  casing  and  leave  only  a  liner  in  the  hole  so  that 
the  packer  may  fill  the  annular  space  between  the  tubing  and  the  water 
string. 

The  water  string  may  leak  because  it  was  not  screwed  together. 
By  screwing  pipe  together,  it  has  been  possible  to  shut  off  a  leak  in  the 
casing. 

If  the  casing  leaks  because  of  a  collapsed  water  string,  it  may  be 
swaged  out;  but  very  often  it  is  difficult  to  repair  such  a  leak.  A  packer 
may  be  used  or  some  cement  forced  through  the  hole  in  the  casing  behind 
the  pipe,  but  often  another  water  string  must  be  landed  deeper  to  shut 
off  the  water,  especially  in  a  drilling  well. 

A  leak  in  the  pipe  may  be  caused  by  a  split  joint  in  the  casing  or  by 
corrosive  waters  eating  through  the  casing  or,  possibly,  line  wear.  If 
the  split  is  large,  a  bridge  capped  with  a  cement  plug  may  be  placed  in 
the  pipe  and  cement  forced  through  the  leak.  If  the  hole  is  small  the 
casing  may  be  ripped  and  cement  forced  in  behind  the  pipe. 


A.    W.   AMBROSE  263 

Where  water  is  leaking  around  the  shoe  of  the  casing  it  may  be  pos- 
sible to  place  a  bridge  several  feet  below  the  shoe  of  the  water  string  and 
then  fill  the  top  of  the  bridge  with  brick,  stone,  or  cement.  After  the 
cement  is  set,  cement  may  be  forced  behind  the  pipe  under  pressure, 
although  usually  this  is  not  an  efficient  and  satisfactory  means.  If  cir- 
culation is  possible,  cement  may  be  pumped  in  behind  the  pipe,  as  de- 
cribed  by  Tough.5  Where  circulation  cannot  be  obtained,  cement  may 
be  forced  through  the  tubing  behind  the  pipe  under  pressure.  Often- 
times when  the  water  is  leaking  around  the  pipe  it  may  be  necessary  to 
cement  a  smaller-sized  string  of  casing  a  few  feet  deeper,  provided  the 
oil  sand  is  not  too  close;  if  the  oil  sand  is  too  close,  redrilling  is  often 
necessary,  after  shooting  the  bottom  of  the  casing,  and  then  recementing 
the  string  at  the  same  depth.  On  some  occasions,  it  has  been  possible 
to  drive  the  pipe  several  feet  to  make  a  lower  formation  shut-off;  also 
a  liner  has  been  landed  with  cement  around  the  outside,  so  as  to  shut 
off  a  water  sand  directly  below  the  casing  shoe. 

Bottom  Water 

Cement  is  recommended  for  plugging  the  bottom  of  the  well  where 
it  has  been  established  that  the  water  is  coming  from  bottom.  Mud-laden 
fluid  has  been  used,  but  is  not  to  be  recommended  generally;  likewise,  a 
lead  seal  or  packer  has  shut  off  bottom  water,  but  the  writer  prefers 
cement. 

Intermediate  Water 

When  intermediate  water  is  present,  the  operator  must  exercise  great 
care  in  protecting  the  upper  oil  sands  while  producing  from  the  lower 
sands  or  vice  versa.  In  producing  oil  from  the  lower  sands  only,  the 
upper  oil  sands  should  be  protected  either  by  the  use  of  mud-laden  fluid 
behind  the  pipe  or  by  pumping  a  liberal  amount  of  cement  behind- the 
water  string.  The  producer  should  make  certain  that  a  sufficient  quan- 
tity is  pumped  in  so  that  the  top  of  the  cement  is  actually  above  the 
upper  oil  zone;  this  will  prevent  the  middle  water  from  entering  the 
upper  oil  horizon. 

Where  a  well  is  making  a  large  amount  of  water  from  an  intermediate 
sand  and  is  producing  from  both  the  upper  and  the  lower  oil  zones,  the 
well  must  be  plugged  up  from  the  bottom  to  above  the  middle  water  and 
production  taken  from  the  upper  sand,  or  else  redrilled  and  a  string  of 
casing  landed  below  the  intermediate  water.  In  plugging,  it  is  best  to 
use  a  large  amount  of  cement  to  protect  the  lower  sand;  and  where  a 
new  string  is  landed  below  the  intermediate  water,  sufficient  cement  or 

6  F.  B.  Tough:  Methods  of  Shutting  Off  Water  in  Oil  and  Gas  Wells.     U.  S.  Bureau 
of  Mines  Bull.  163. 


264  ANALYSIS    OF   OIL-FIELD    WATER    PROBLEMS 

mud-laden  fluid  should  be  placed  behind  the  pipe  to  assure  proper  pro- 
tection of  the  upper  oil  zone. 

Goodrich  suggests  the  use  of  a  liner  with  packers  on  the  outside  of  the 
pipe  at  the  top  and  bottom  to  shut  off  an  intermediate  water.  The 
liner  would  be  set  opposite  the  water  sand,  as  the  packers  would  be 
expected  to  confine  the  water  to  the  sand.  Where  the  water  has  any 
appreciable  head,  it  is  very  doubtful  if  this  method,  in  the  majority  of 
cases,  will  prove  satisfactory. 

Edge  Water 

The  following  are  suggested  methods  for  restraining  encroaching 
edge  water:  (1)  Use  of  compressed  air  to  hold  back  the  water  by  forcing 
air  into  those  wells  nearest  the  edge-water  line,  thus  holding  back  the 
water  while  allowing  increased  production  in  the  wells  up  slope.  (2) 
Drilling  ahead  of  the  approaching  water  and  plugging  the  well  as  soon 
as  the  water  becomes  troublesome. 

For  the  purpose  of  obtaining  a  maximum  production,  a  careful  study 
should  be  made  of  drilling  costs  and  production  in  order  to  arrive  at  an 
economic  cost  balance  that  will  determine  the  maximum  number  of  wells 
that  can  be  drilled  in  order  that  the  production  may  yield  the  largest 
profit  possible.  In  short,  the  encroaching  edge  water  will  entrap  much 
of  the  oil  underground,  so  the  operator  should  plan  to  get  the  greatest 
profit  per  barrel  of  production.  In  the  case  of  edge  water,  this  study 
should  be  made  before  water  becomes  the  master. 

Edge  water  may  occur  in  the  top,  middle,  or  bottom  oil  sands.  If 
edge  water  occurs  in  the  top  sand  and  the  water  has  advanced  to  the  well, 
it  is-,  of  course,  a  matter  of  treating  the  upper  sand  as  a  top-water  sand 
and  then  making  a  shut  off  below  it. 

Where  there  are  several  producing  sands  and  the  edge  water  occurs 
in  an  intermediate  sand,  it  may  be  handled  by  plugging,  with  cement, 
from  the  bottom  to  a  point  above  the  water  sand,  after  which  the  operator 
can  produce  from  the  top  sand  in  that  well.  In  doing  this,  great  care 
should  be  taken  that  no  water  is  allowed  permanent  access  to  the  lower 
oil  zones.  Another  way  is  to  redrill  the  well  and  land  a  water  string 
below  the  edge-water  sand  and  the  well  made  to  produce  from  the  lower 
zone.  It  is  important  in  such  a  case  that  the  top  oil  sands  be  properly 
protected. 

If  edge  water  appears  in  the  bottom  sand  of  a  well,  it  should  be  plugged 
off  by  cement  and  production  taken  from  the  sands  above. 

Water  in  the  Base  of  an  Oil  Sand  or  in  a  Lenticular  Sand 

The  operator  should  be  certain  that  the  water  and  oil  are  not  separated 
by  a  small  break  before  deciding  that  the  water  occurs  in  the  base  of  an 


DISCUSSION  265 

oil  sand.  It  is  very  difficult  to  place  a  thin  cement  plug  of  an  exact 
thickness  by  ordinary  dump  bailer  methods,  but  cement  should  be  used 
and  the  well  plugged  in  stages  and  tested.  In  each  test  the  operator 
should  see  if  the  cement  is  hard  and  should  plug  only  a  few  feet  at 
a  time 

The  McDonald  method  of  shutting  off  water  in  an  oil  well  has  been 
very  successful  in  the  Illinois  field  and  has  been  described  in  a  bulletin 
of  the  Illinois  Geological  Survey.6  A  description  is  also  given  in  an 
article  by  Tough.7  When  the  water  and  oil  together  occur  in  the  same 
sand,  the  application  of  the  McDonald  method  or  any  other  can  at  best 
only  delay  its  approach,  for  eventually  water  will  cause  much  trouble 
and  expense. 

A  lens  of  water  may  occur  any  place  in  the  productive  zone  and 
should  be  handled  as  a  top,  bottom,  or  middle  water,  depending  on  its 
location. 

DISCUSSION 

R.  A.  CONKLING,*  St.  Louis,  Mo. — We  have  found  it  more  helpful 
to  observe  the  amount  of  water  by  the  sands  above  the  oil  than  to  analyze 
the  water.  A  well  in  Texas  came  in  at  1000  bbl.  but  in  about  a  week 
began  to  show  water.  After  the  fourth  day  about  30  bbl.  of  water  were 
produced.  The  field  department  thought  it  was  bottom  water  and 
wanted  to  plug  immediately.  It  has  been  producing  for  the  last  three 
months  and  has  been  making  about  the  same  amount  of  water  that  the 
water  sands  were  thought  able  to  produce. 

In  another  case  we  went  through  a  couple  of  water  sands  and  ran 
into  an  oil  sand  about  200  ft.  below.'  We  have  been  trying  to  get  the 
field  department  to  repair  that  well,  because  we  know  the  water  will  go 
down  when  we  get  to  the  shallow  oil  sand.  This  shows  that  the  geologist 
in  the  field  should  keep  close  records  while  drilling,  for  such  records  will 
help  solve  problems  that  will  come  up  later. 

E.  DEGOLYER,  New  York,  N.  Y. — One  point  in  connection  with  the 
question  of  bottom  water  that  has  not  been  considered  much  in  American 
practice  is  keeping  down  the  water  by  checking  the  flow  of  a  well.  In 
Mexico,  especially  in  the  southern  part  of  the  Tampico-Tuxpam  region, 
oil  occurs  in  very  porous  limestone  and  probably  moves  with  an  ease  and 
freedom  that  is  not  equalled  in  any  kn«wn  field  of  the  United  States. 


6  F.  H.  Kay:  Petroleum  in  Illinois  in  1914-1915.     Illinois  State  Geol.  Survey 
Bull.  33  (1916)  87-88. 

7  F.  B.  Tough:  Methods  of  Shutting  OS  Water  in  Oil  and  Gas  Wells.     U.  S. 
Bureau  of  Mines  Bull  163,  82-85. 

*  Head  Geologist,  Roxana  Petroleum  Corpn. 


266  *  ANALYSIS   OP   OIL-FIELD   WATER   PROBLEMS 

Under  the  oil  is  the  bottom  water,  which  is  practically  the  only  water. 
Conditions  are  more  or  less  artesian.  If  an  oil  deposit  is  trapped  over 
water  having  an  artesian  head  in  an  anticline,  you  have  a  condition  simi- 
lar to  that  existing  in  Mexico.  In  a  certain  field  where  the  deposit  of  oil 
was  possibly  only  a  few  feet  thick,  the  entire  field  was  practically  ruined 
by  trying  to  make  10,000-bbl.  wells  out  of  what  were  probably  100-bbl. 
wells.  One  well  produced  6000  bbl.  of  clean  oil  in  the  first  few  hours, 
but  water  then  broke  through  and  in  three  or  four  minutes  the  product 
turned  through  the  various  shades  from  jet  black  to  a  dirty  lemon  yellow 
as  the  percentage  of  water  increased  and  the  well  was  ruined. 

In  one  of  the  larger  fields,  when  a  well  making  18,000  bbl.  of  clean  oil 
began  to  show  water,  its  production  was  reduced  to  16,000  bbl.,  which 
checked  the  flow  of  water  for  a  few  months.  Whenever  water  appeared, 
the  production  was  checked  and  the  oil  cleared.  The  well  is  now  pro- 
ducing 900  to  1000  bbl.  of  clean  pipe-line  oil.  Over  2,500,000  bbl.  of 
clean  oil  have  been  obtained  since  water  first  appeared  by  thus  nursing 
the  well  along.  We  have  made  a  set  of  curves  showing  temperature, 
water  and  sediment,  flow-line  pressures,  etc.,  that  demonstrates  clearly 
the  conditions  governing  occurrence  of  oil  in  Mexico. 

Until  the  Potrero  del  Llano  well  began  to  show  water  there  were  only 
slight  variations  in  the  temperature  of  the  oil.  When  water  appeared, 
the  temperature  of  the  oil  increased  18°  to  20°  F.  within  twenty- 
four  hours. 

MR.  REILLEY. — Isn't  it  just  as  necessary  to  curb  a  well  making  a 
large  volume  of  gas  with  the  oil  as  it  would  be  to  curb  a  well  with  less  gas 
making  the  same  volume  of  water? 

E.  DEGOLYER. — My  whole  consideration  of  this  subject  bears  on 
the  question  of  raising  the  critical  cone  in  the  water  table  and  of 
lowering  the  top  of  that  cone.  I  think  that  if  there  is  a  lot  of  gas  with 
the  oil,  the  cone  is  likely  to  be  much  sharper  than  with  the  dead,  heavy 
oil.  The  worst  condition  resulting  from  water  coming  is  when  the 
crest  of  the  cone  reaches  the  bottom  of  the  casing  in  a  well  and  thus  cuts 
off  any  remaining  oil. 

R.  VAN  A.  MILLS,*  Washington,  D.  C. — The  Bureau  of  Mines  has 
made  a  large  number  of  experiments  with  oils  of  different  viscosities 
under  different  rates  of  recovery  that  tend  to  substantiate  many  of  Mr. 
DeGolyer's  remarks.  It  is  necessary  to  study  the  differences  in  the  be- 
haviors of  oils  of  different  viscosities  as  influenced  by  the  rates  of  recovery 
under  various  conditions.  In  doing  this  work  the  Bureau  of  Mines  is 
studying  the  relative  times  required  to  form  water  cones  under  different 
conditions  of  flow,  together  with  the  time  required  for  the  cones  to 

*  Petroleum  Technologist,  U.  S.  Bureau  of  Mines. 


DISCUSSION  267 

flatten  out  under  retarded  conditions  of  flow,  as  well  as  during  periods 
of  rest.  As  a  rule,  water  cones  are  accentuated  by  increased  rates  of  flow, 
and  decreased  or  eliminated  by  reductions  in  the  rates  of  flow.  My 
experiments  indicate  that  under  certain  conditions  water  cones  form 
more  readily  with  dead  oils  than  with  oils  heavily  charged  with  gas. 
In  attacking  these  problems  it  is  dangerous  to  generalize  because  of  the 
many  factors  and  different  sets  of  limiting  conditions  involved  in  the 
different  fields. 

R.  A.  CONKLING. — Our  department  has  an  exploration  geologist, 
who  has  charge  of  the  drilling  of  all  wells;  the  total  depth  is  always  sent 
out  from  the  St.  Louis  office.  A  geologist  in  the  field  sends  in  samples 
and  works  up  as  much  data  as  possible.  We  have  a  lease  1  mi.  long  and 
y±  mi.  wide  with  four  operators  operating  around,  offsetting  it.  On  the 
north,  the  wells  began  making  water  almost  as  soon  as  they  were  drilled 
in.  Wells  come  in  from  1000  to  3000  bbl.  Until  a  week  ago,  we  did  not 
have  0.5  per  cent,  water,  by  analysis,  in  all  of  the  oil  on  that  lease;  the 
adjoining  leases  have  from  5  per  cent,  to  100  per  cent,  water;  three  wells 
are  all  water. 

We  simply  stop  the  wells  above  water  level  when  the  edge  water  has 
just  begun  to  come;  the  field  department  will  plug  back,  because  there 
is  plenty  of  sand  and  the  water  will  soon  rise  to  that  level. 

At  one  time  30,000  bbl.  of  crude  oil  were  turned  out  by  one  operator. 
He  did  not  have  any  place  to  keep  it  so  he  had  to  turn  it  loose  to  take 
care  of  the  other  oil.  That  is  what  we  save  the  company. 

In  another  case  the  field  department  struck  water  and  wanted  to 
know  whether  to  plug  back.  It  was  above  our  water  level,  and  we 
had  two  other  wells  going  down  to  deep  sand  nearby.  Knowing  that 
that  was  not  the  true  water  level,  we  told  them  to  bail  for  a  week.  After 
bailing  four  days,  the  water  was  gone,  so  we  deepened  the  wells  to  the 
proper  horizon. 

R.  VAN  A.  MILLS. — In  considering  the  determination  of  the  source  of 
oil-well  water  by  chemical  analysis,  one  must  bear  in  mind  the  fact  that 
the  water  produced  from  an  oil-bearing  horizon  in  a  new  field  may  be 
different  from  the  water  produced  from  that  same  bed  a  year  or  two  later; 
not  because  water  has  leaked  into  that  bed  through  wells,  but  because 
the  water  in  that  bed  has  undergone  induced  changes.  Water  associated 
with  oil  and  gas  in  the  pays  undergoes  induced  concentration  through 
the  removal  of  water  vapor  in  expanding  gases,  the  concentration  being 
accompanied  by  changes  in  the  relative  proportions  of  the  dissolved 
constituents.  The  fact  is  emphasized  that  differences  in  the  analyses  of 
waters  collected  from  the  same  well  at  different  times  do  not  necessarily 
indicate  the  infiltration  of  top  or  bottom  water,  especially  if  edge  water 
accompanied  the  oil  and  gas  in  the  pay  when  the  well  was  brought  in. 


268  ANALYSIS   OP   OIL-FIELD   WATER   PROBLEMS 

Again,  we  must  consider  the  relations  that  the  viscosities  of  oils, 
the  pressures  and  proportions  of  gases  accompanying  the  oils,  and  the 
textures  and  bedding  of  sands  bear  to  the  differential  movements  between 
oils  and  water.  For  instance,  the  differential  movements  between 
Appalachian  crude  oils  of  low  viscosity  and  water  are  comparatively 
slight,  whereas  with  oils  of  higher  viscosities  the  differential  movements 
are  so  pronounced  as  to  lead  operators  to  think  that  wells  or  entire  fields 
have  gone  entirely  to  water,  when  in  reality  the  wells  are  affected  only 
by  water  cones,  a  large  part  of  the  oil  still  remaining  to  be  recovered. 
Experiments  show  that  an  Appalachian  oil  of  low  viscosity  migrates 
readily  under  the  propulsion  of  hydraulic  currents,  whereas  under  the 
same  conditions  a  California  crude  of  high  viscosity  fails  to  migrate  at 
all.  Obviously  the  effect  of  water  on  oil  recovery  depends  largely  on 
the  viscosities  of  the  oils — the  more  viscous  the  oils,  the  more  detrimental 
is  the  effect  of  water. 

Oil  is  propelled  to  wells  by  the  expansive  force  of  gas.  Under  certain 
conditions  the  oil  is  thus  propelled  to  the  wells  ahead  of  water,  but 
as  the  gas  is  exhausted,  this  relationship  may  change  so  that  the  water 
advances  to  the  wells  ahead  of  the  oil.  This  is  illustrated  by  gushers 
in  which  we  have  slight,  if  any,  shows  of  water  until  a  large  proportion 
of  the  gas  is  exhausted. 

The  sizes  of  pores  through  which  the  fluids  pass  also  have  a  decided 
influence  on  the  relations  of  water  to  the  recovery  of  oil.  Under  various 
conditions,  the  differential  movements  between  oil  and  water  are  accentu- 
ated as  the  sizes  of  the  pores  are  diminished.  Where  the  sizes  of  pores 
are  sufficiently  diminished  by  induced  cementation,  the  recovery  of  oil 
may  be  greatly  retarded  or  entirely  prevented  It  is  imperative  that 
we  consider  these  fundamental  principles  in  attacking  oil-field  water 
problems. 


OIL-FIELD  BRINES  269 


Oil-field  Brines 

BY  CHESTER  W.  WASHBURNE,  NEW  YORK,  N.  Y. 

(St.  Louis  Meeting,  September,  1920) 

RECENTLY,  Messrs.  Mills  and  Wells1  published  a  thorough  chemical 
study  of  the  waters  associated  with  oil  in  parts  of  the  Pennsylvania, 
Ohio,  and  West  Virginia  region.  Many  of  their  conclusions  are  of  gen- 
eral application  and  the  writer  wishes  to  discuss  some  of  these. 

Messrs.  Mills  and  Wells  show  that  the  composition  of  the  deep  brines 
of  the  Appalachian  fields  is  such  as  would  be  produced  by  the  evaporation 
of  sea  water  and  the  precipitation  of  sodium  chloride,  combined  with 
reactions  with  hydrocarbons  and  other  substances.  The  brines  are 
altered,  also,  by  considerable  mixing  with  meteoric  water.  They  give 
good  reasons  for  believing  that  the  concentration  of  the  brines  was  pro- 
duced by  evaporation  in  the  rock  pores  induced  by  migrating  gas,  much 
of  which  probably  escaped  to  the  surface  of  the  ground. 

This  hypothesis  was  considered  by  the  writer  in  a  former  paper,2 
in  which  main  stress  was  laid  on  a  second  hypothesis,  that  the  excess 
of  chlorine  in  the  deep  brines  may  have  been  due  to  the  entrance 
of  solutions  rich  in  magnesium  and  calcium  chloride  which  ascended 
from  a  deep,  possibly  intratelluric,  source.  Messrs.  Mills  and  Wells 
present  good  arguments  for  the  first  hypothesis.  Underground  evap- 
oration by  ascending  gases  probably  will  be  accepted  as  the  best 
available  explanation  of  the  concentration  and  composition  of  deep  well 
waters. 

They  have  not  considered  the  possibility  that  salt  waters  in  deep 
sands  may  be  concentrated  by  the  diffusion  of  water  vapor  through  gas 
into  shale.  The  writer  has  given  reasons3  for  believing  that  capillary 
forces  concentrate  gas  and  oil  in  the  larger  openings  of  rock,  such  as  the 
pores  of  sandstones  embedded  in  shale.  The  gas  underground  must  be 
nearly  saturated  with  water  vapor  at  all  times,  because  it  always  is  in 
contact  with  the  interstitial  water  of  enclosing  shales  and  of  the  sand- 
stone. Experimental  studies  of  soil  moisture  have  shown  that  approxi- 


1  R.  Van  A.  Mills  and  Roger  C.  Wells:  The  Evaporation  and  Concentration  of 
Waters  Associated  with  Petroleum  and  Natural  Gas.     U.  S.  Geol.  Survey  Butt.  693 
(1919). 

2  C.  W.  Washburne:  Chlorides  in  Oil-field  Waters.     Trans.  (1914)  48,  689,  690. 

3  C.  W.  Washburne:  The  Capillary  Concentration  of  Oil.    Trans.  (1914)  60,  829. 


270  OIL-FIELD   BRINES 

mately  saturated  soil  air  deposits  its  moisture  on  concave  water  surfaces 
of  sharp  curvature,  such  as  the  capillary  surfaces  in  the  pores  of  clay, 
while  it  is  absorbing  or  evaporating  water  from  concave  surfaces  of 
larger  curvature,  as  in  sands,  where  the  water  films  are  relatively  broad.4 
In  this  way  there  is  probably  a  slow  migration  of  water  vapor  from  sand- 
stone into  shale.  The  process  is  essentially  a  diffusion  of  water  vapor 
through  gas.  It  is  effective  only  to  the  extent  that  the  shale  contains 
gas  to  exchange  for  the  water  it  receives  from  the  sand.  Nevertheless, 
this  process  of  vapor  diffusion  operating  through  geological  periods  would 
be  a  potent  factor  in  evaporating  the  water  in  sands.  It  would  operate 
in  either  stagnant  or  moving  gas,  and  is  regarded  as  supplemental  to 
the  process  of  evaporation  by  convection  in  moving  currents  of  gas 
postulated  by  Messrs.  Mills  and  Wells.  This  process  of  diffusion  of 
water  vapor  and  its  condensation  in  shale  would  increase  the  concentra- 
tion of  the  brines. 

ORIGIN  OF  SALT  CORES 

Messrs.  Mills  and  Wells  carry  their  theory  to  its  ultimate  limit  in 
trying  to  explain  the  origin  of  the  salt  domes  of  the  Gulf  Coast  and  other 
regions.  They  show  that  the  volume  of  gas  required  to  deposit  salt 
under  a  pressure  of  100  atmospheres  and  " under  reasonable  conditions" 
is  from  145  to  1550  times  the  volume  of  salt  deposited.  The  smaller 
figure  is  for  temperatures  of  100°  C.  and  the  larger  figure  is  for  40°  C. 
From  the  depth  of  the  upper  part  of  the  salt  cores,  the  temperature  of 
deposition  probably  did  not  exceed  40°  C.  unless  deep-seated  hot  waters 
were  involved;  hence,  the  volume  of  gas  required  would  be  about  1500 
times  the  volume  of  salt. 

Do  they  realize  that  the  volume  of  most  of  the  salt  cores  probably  is 
over  one  cubic  mile?  Some  of  the  domes,  such  as  Humble  and  South 
Dayton,  have  proved  volumes  of  five  cubic  miles  or  more,  and  possibly 
of  many  times  this  amount  if  they  extend  as  far  downward  as  commonly 
thought.  Could  the  required  1500  or  7500  cu.  mi.  of  gas  be  furnished 
by  the  thick  sediments  underlying  the  region  tributary  to  any  salt  core? 
If  this  volume  of  gas,  measured  under  100  atmospheres  pressure,  escaped 
in  one  geological  period  at  the  site  of  any  salt  dome,  it  could  be  only 
through  vertical  channels  which  would  necessarily  be  so  free  and  open 
that  there  could  have  been  no  accumulation  of  oil  and  gas  at  these  places. 
Moreover,  the  salt  cores  are  at  least  a  few  thousand  feet  in  height  and 
cut  so  many  water-bearing  sands  that  the  writer  doubts  if  any  process 
could  concentrate  the  solutions  to  saturation.  The  water  in  these  sands 

4  Lord  Kelvin.  Referred  to  by  Lyman  J.  Briggs:  The  Mechanics  of  Soil  Moisture. 
U.  S.  Dept.  of  Agric.,  Div.  of  Soils,  Bull.  10  (1897)  12,  with  reference  to  Maxwell: 
Theory  of  Heat,  287.  Important  later  references  not  at  hand. 


CHESTER  W.   WASHBtTRNE  271 

generally  is  only  moderately  saline,  and  commonly  is  under  artesian 
head.  At  least  some  of  the  sands  outcrop  in  higher  country  farther 
inland.  Some  of  them  furnish  potable  artesian  water  in  the  same  gen- 
eral region,  but  not  in  the  oil  fields,  where  potable  water  occurs  only  in 
the  shallower  sands,  although  a  few  of  the  flows  of  deep  waters  are  only 
moderately  saline. 

The  region  where  the  sands  outcrop  has  not  been  submerged  since 
they  were  deposited  by  fresh-water  streams.  The  region  of  most  of  the 
productive  salt  domes  probably  was  temporarily  covered  by  the  sea  in 
Neocene  time.  Possibly  the  coastal  parts  of  many  of  the  oil  sands  are 
marine;  marine  shells  occur  in  the  lower  water-bearing  sands  of  the 
Goose  Creek  field.  Some  of  the  sands  appear  to  be  local  and  not  to 
extend  far  inland,  being  possibly  beach  sands  that  spread  laterally  along 
the  Tertiary  sea  shores.  Other  lenticular  sands  may  occur.  However, 
there  are  several  wide-spread  sands  and  it  is  probable  that  their  outcrop 
always  was  higher  than  the  region  of  productive  salt  cores.  Hence,  the 
water  in  the  outcropping  sands  always  tended  to  flow  toward  the  sea, 
maintaining  a  certain  degree  of  freshness  in  the  sands.  If  this  inference 
is  correct,  it  would  be  impossible  for  salt  cores  to  grow  upward  across 
the  sands  by  any  process  of  precipitation,  because  there  must  have  been 
sufficient  artesian  circulation  in  the  sands  to  keep  the  waters  dilute. 
This  artesian  circulation  would  be  set  up  as  soon  as  fissures  or  other 
vertical  channels  were  opened  for  the  ascent  of  the  hypothetical  salt 
solutions.5 

The  mixing  of  the  meteoric  waters  from  the  sands  with  the  hypothet- 
ical rising  salt  solutions  would  keep  the  latter  from  reaching  a  state  of 
saturation.  All  theories  of  the  chemical  origin  of  the  salt  cores  postulate 
a  period  of  free  upward  circulation  at  the  loci  of  the  domes.  Such  free- 
dom to  move  upward  would  release  the  partly  meteoric  waters  in  the 
Tertiary  sands  and  would  let  them  circulate  more  rapidly  down  the  dip, 
increasing  their  freshness.  These  waters  would  enter  any  vertical  fis- 
sures and  would  prevent  the  deposition  of  salt  therein;  in  fact,  they  prob- 
ably would  be  fresh  enough  to  dissolve  any  salt  previously  deposited. 
Hence  it  seems  impossible  that  the  salt  cores  could  have  been  precipi- 
tated from  waters  that  rose  along  fissures  cutting  all  of  these  water- 
bearing sands.  A  better  explanation  is  that  presented  by  van  der 
Gracht,6  that  the  salt  cores  are  essentially  intrusive  masses  that  were 


6  Vigorous  natural  artesian  circulation  of  this  type  is  taking  place  at  the  salt 
dome  at  West  Point,  Tex.  This  dome  is  surrounded  by  a  ring-shaped  valley  full  of 
fresh-water  springs.  The  water  comes  from  sands  in  the  Wilcox  formation.  There 
are  also  some  salty  springs.  See  E.  De  Golyer,  JnL  Geol  (1919)  28,  653. 

6  S.  W.  Assoc.  Petrol.  Geol.  Bull  1  (1917)  85.  See  also  G.  S.  Rogers:  The  Origin 
of  the  Salt  Domes  of  the  Gulf  Coast  of  Texas  and  Louisiana.  Econ.  Geol.  (1918)  13, 
447;  DeGolyer,  Trans.  (1919)  61,  456;  Rogers,  Econ.  Geol  (1919)  14,  178. 


272  OIL-FIELD   BRINES 

\ 

squeezed  up  in  semiplastic  condition  from  hypothetical  salt  beds  in  the 
Permean  or  other  underlying  strata. 

There  seem  to  be  only  two  dubious  ways  by  which  the  fresh-water 
sands  could  be  sealed  sufficiently  to  prevent  them  from  flooding  the 
fissures.  The  first  would  be  by  clogging  their  pores  with  salts  next  to 
fissures  in  which  large  quantities  of  warm  gases  were  rising  from  below. 
This  method  might  effectively  seal  off  the  sands  that  contained  nearly 
saturated  solutions,  but  many  sands  are  involved,  and  it  seems  probable 
that  some  of  these  that  outcrop  inland  must  have  furnished  strong  flows 
of  comparatively  fresh  water,  which  would  prevent  their  becoming 
clogged  by  salt.  The  second  way  is  as  follows:  Gas  rising  from  great 
depths  tends  to  maintain  some  of  its  original  pressure  by  expanding. 
The  gas  rising  in  a  fissure  might  be  under  higher  pressure  than  the  water 
in  any  artesian  sand  cut  by  the  fissure.  It  would  seem,  therefore,  that 
the  gas  would  enter  the  water  sands  and  drive  back  the  water.  The  gas 
would  enter  the  sands  to  a  certain  extent,  especially  through  the  larger 
pores  where  capillarity  exerts  less  resistance  to  flow.  The  gas  could  not 
hold  the  water  back  in  the  finer  pores  of  the  same  sand.  Thus,  circula- 
tions would  be  set  up  whereby  water  in  the  sand  would  be  exchanged  for 
gas  in  the  fissure,  until  the  pressure  in  the  sand  nearly  equaled  that  in 
the  fissure  after  which  large  quantities  of  water  could  enter  the  fissure 
from  the  sand.  This  method  would  be  no  more  effective  than  an  attempt 
to  use  gas  to  seal  off  a  water  sand  in  a  deep  well. 

In  other  words,  it  seems  impossible  to  postulate  the  precipitation  of 
salt  from  solutions  ascending  in  fissures  many  thousand  feet  across  the 
broken  edges  of  the  Tertiary  strata  of  the  Gulf  Coast.  There  are,  and 
always  have  been,  too  many  sands  in  these  formations  that  contain  fresh 
or  moderately  saline  artesian  waters,  which  would  enter  the  fissures  and 
would  prevent  precipitation  of  salt. 

ORIGIN  OF  GYPSUM  IN  SALT  DOMES 

Thick  bodies  of  gypsum  are  present  near  the  tops  of  some  of  the  salt 
cores  of  the  Gulf  Coast.  These  generally  overlie  the  salt,  having  thus 
the  same  position  that  is  commonly  occupied  by  gypsum  in  the  salt 
mines  of  Germany  and  other  places.  This  suggests  that  the  gypsum 
may  have  ascended  en  masse  on  top  of  the  intrusive  body  of  salt,  but  it 
is  not  a  conclusive  argument  against  other  theories. 

Messrs.  Mills  and  Wells  have  observed  the  deposition  of  calcium 
sulfate  in  the  bottom  of  wells,  where  sulfate  waters  had  leaked  down  the 
casing  from  upper  levels  and  had  mixed  with  brines  rich  in  calcium 
chloride.  This  suggests  that  the  tops  of  the  salt  cores  of  the  Gulf  Coast 
may  have  been  the  places  where  descending  sulfate  waters  mingled  with 
brines  of  the  oil-field  type  rich  in  calcium  chloride,  which  would  cause 
the  precipitation  of  gypsum  at  that  horizon.  The  latter  explanation  is 


CHESTER   W.    WASHBURNE 


273 


necessary  only  if  one  adopts  the  theory  that  the  salt  cores  were  deposited 
from  solutions.  It  is  a  possible  source  of  the  gypsum  under  either  theory. 
E.  DeGolyer,7  referring  to  the  chemical  work  of  Frank  K.  Cameron,8 
shows  that  the  gypsum  may  have  been  deposited  against  the  salt  mass 
where  the  sulfate-bearing  waters  dissolved  sodium  chloride  until  they 
became  highly  concentrated  therewith.  Cameron  showed  that  in  a 
highly  concentrated  solution  of  sodium  chloride  gypsum  is  much  less 
soluble  than  in  a  moderately  concentrated  solution.  This  doubtless 
would  be  an  efficient  method  of  precipitating  the  gypsum  which  had  been 
dissolved  from  surrounding  strata  by  moderately  concentrated  solutions 
of  sodium  chloride.  However,  a  study  of  the  following  table  by  Cameron, 
copied  from  DeGolyer,9  shows  that  the  addition  of  sodium  chloride, 
however  great  the  amount,  could  not  precipitate  the  gypsum  dissolved 

Solubility10  of  Calcium  Sulfate  in  Aqueous  Solutions  of  Sodium  Chloride 

a*  23° 


NaCl, 

Grams  per 
Liter 

CaSO,, 

Grams  per 
Liter 

Gypsum, 
Grams  per 
Liter 

NaCl, 
Grama  per 
Liter 

CaS04, 
Grams  per 
Liter 

Gypsum, 
Grams  per 
Liter 

0.99 

2.37 

2.99 

129.50 

7.50 

9.42 

4.95 

3.02 

3.82 

197.20 

7.25 

9.17 

10.40 

3.54 

4.48 

229.70 

7.03 

8.88 

30.19 

4.97 

6.31 

306.40 

5.68 

7.19 

49.17 

5.94 

7.51 

315.55" 

5.37° 

6.97' 

75.58 

6.74 

8.53 

a  The  solution  in  this  case  was  in  contact  with  both  gypsum  and  sodium  chloride 
in  the  solid  phase. 

from  surrounding  strata  by  solutions  containing  less  than  about  40  gm. 
per  liter  of  sodium  chloride.  In  other  words,  the  original  solution  of 
the  gypsum  must  have  been  effected  by  solutions  of  sodium  chloride 
stronger  than  40  gm.  per  liter.  This  restriction  may  limit  the  possible 
source  of  gypsum  to  a  small  zone  immediately  surrounding  the  salt  mass, 
because  there  is  reason  to  believe  that  most  of  the  water  in  sands  remote 
from  the  salt  cores  contain  less  than  40  gm.  per  liter  of  common  salt. 
The  table  also  indicates  that  anhydrite  would  be  the  mineral  generally 
deposited,  rather  than  gypsum,  but  the  former  readily  converts  into  the 
latter  under  certain  underground  conditions.  Both  minerals  occur  in 
the  cap  rocks. 

7  Origin  of  the  Cap  Rock  of  the  Gulf  Coast  Salt  Domes.    Econ.  Geol  (1918)  13, 
618-619. 

8  Various  papers,  U.  S.  Dept.  of  Agric.,  Div.  of  Soils,  Bull.  18,  33  and  49;  also 
Jnl  Phys.  Chem.  (1901)  6. 

9  Loc,  cit. 

10  Frank  K.  Cameron:    Solubility  of   Gypsum  in  Aqueous  Solutions  of  Sodium 
Chloride.     U.  S.  Dept.  of  Agric.,  Div.  of  Soils,  Butt.  18  (1901)  25-45  (Table  IX). 

VOL.  IAV. 18. 


274  OIL-FIELD  BRINES 

ORIGIN  OF  GYPSUM  IN  THE  RED  BEDS 

The  structure  of  the  thick  masses  of  gypsum  found  in  the  Red  Beds 
of  the  Western  part  of  the  United  States  and  other  regions  is  strongly 
suggestive  of  a  secondary  origin.  Some  gypsum  beds  spread  with  fairly 
uniform  thickness  over  broad  areas,  as  the  main  gypsum  bed  of  the 
Permean  of  southern  Oklahoma.  Beds  of  this  type  appear  to  have  been 
deposited  in  semi-enclosed  basins,  possibly  near  the  margins  of  the  sea. 
In  other  cases,  remote  from  known  seas  of  the  same  age  as  the  gypsum, 
as  in  the  Big  Horn  Basin  of  Wyoming  and  south  of  the  Owl  Creek  Moun- 
tains, the  gypsum  beds  in  the  Triassic  Red  Beds  are  lenticular  and  irregu- 
lar. There  is  much  contortion  of  layers  and  considerable  impurity. 

Frequently  the  surrounding  beds  have  forms  which  suggest  that  they 
have  been  shoved  apart  by  the  more  or  less  concretionary  growth  of  the 
mass  of  gypsum.  The  bedding  is  imperfect  and  the  individual  layers 
of  the  gypsum  are  imperfectly  developed,  and  are  exceedingly  variable 
in  thickness.  It  is  quite  possible  that  these  gypsum  beds  have  grown 
by  accretion  through  the  deposition  of  calcium  sulfate  precipitated  by 
the  mingling  of  underground  brines  rich  in  calcium  chloride  with  sulfate 
waters  of  meteoric  origin.  Some  of  these  lenses  of  gypsum  give  the  im- 
pression of  having  been  deposited  in  desert  lakes  and  of  having  under- 
gone a  secondary  growth  after  burial,  in  the  same  way  that  concretions 
of  the  pure  mineral  type  grow  in  sedimentary  rocks  by  shoving  the 
matrix  aside. 

x 

ORIGIN  OF  LIMESTONE  CAPS 

The  uppermost  level  of  a  salt  core  commonly  is  a  bed  of  porous  lime- 
stone, which  varies  in  thickness  from  20  to  over  100  ft.  (6  to  30  m.) 
No  fossils  have  been  observed  in  this  limestone.  Fragments  of  it  suggest 
that  the  limestone  is  of  secondary  origin  and  that  it  was  deposited  from 
solution.  Its  deposition  might  be  explained  either  on  the  theory  of  the 
mixing  of  oil-field  brines  with  waters  containing  carbonates  or  from  the 
release  of  carbon  dioxide  carried  in  solution  by  ascending  brines.  It  is 
possible  also  that  the  limestone  caps  may  have  lain  above  the  gypsum 
of  salt  in  their  original  positions  in  the  Permean  or  other  deeply  buried 
formation.  However,  secondary  limestones  are  rare  in  the  Permean  of 
western  Texas. 

There  are  difficulties  in  both  of  these  explanations.  If  the  limestone 
caps  were  deposited  from  solution,  it  is  hard  to  see  why  they  do  not 
extend  generally  down  the  sides  of  the  salt  cores  and  why  the  deposition 
of  lime  did  not  spread  laterally  between  the  sand  grains,  converting  the 
sandstones  into  solid  bodies  of  calcareous  sandstone  or  sandy  limestone, 
instead  of  leaving  them  so  completely  friable  and  uncemented.  In  some 
cases,  DeGolyer  says,  the  limestone  caps  extend  at  least  a  little  way 


CHESTER   W.    WASHBURNE  275 

down  the  sides  of  the  domes  and  have  what  appears  to  be  a  "thimble 
shape." 

The  theory  that  the  limestone  caps  rose  on  the  top  of  intrusive  masses 
seems  hard  to  accept,  because  there  is  practically  no  evidence  of  the 
breaking  up  of  the  cap  by  faulting  or  brecciation,  which  would  seem  to 
be  a  necessary  accompaniment  of  its  ascent  at  the  top  of  the  intrusive 
salt  plug.  The  cap  rock,  however,  may  be  broken  and  fissured  more 
than  is  commonly  thought,  since  in  studying  Coastal  well  logs  one  can 
recognize  only  large  displacements.  The  locally  high  production  of  oil 
or  sulfur  from  the  cap  rock  may  be  an  indication  of  brecciation  or  ex- 
tensive fissuring. 

Limestone  caps  do  not  characteristically  occur  in  great  thickness 
above  the  salt  and  gypsum  beds  that  have  been  explored  in  Germany 
and  other  foreign  fields.  Thin  caps  of  this  kind  occur  in  some  places 
above  thick  beds  of  rock  salt,  but  I  do  not  know  of  any  salt  mine  in 
the  world  where  there  is  a  cap  of  secondary  limestone  that  approaches 
the  thickness  of  these  caps  on  the  salt  cores  of  the  Gulf  Coast.  The  origin 
of  the  limestone  caps  of  the  salt  cores  remains  an  open  question. 

Lately,  DeGolyer11  has  suggested  that  the  calcium  carbonate  of  the 
cap  rock  may  have  been  precipitated  by  the  action  of  sodium  chloride, 
basing  his  suggestion  on  Cameron's  observation  that  very  concentrated 
solutions  of  sodium  chloride  can  hold  less  calcium  bicarbonate  than 
weaker  solutions.  He  quotes  the  following  figures: 

SOLUBILITY  OF  CALCIUM  BICARBONATE  IN  AQUEOUS  SOLUTIONS  OF  SODIUM  CHLORIDE 

SODIUM  CHLOR:DE,  CALCIUM  BICARBONATE, 

GRAMS  PER  LITER  GRAMS  PER  LITER 

0.0  0.06 

39.62  0.101 

267.60  0.04 

The  experiments  were  made  in  equilibrium  with  atmospheric  air. 
Their  direct  application  to  the  problem  is  weakened  by  our  ignorance 
of  the  amount  of  carbon  dioxide  in  the  underground  gases  that  accom- 
panied the  solutions  which  deposited  the  limestone  caps.  The  table 
seems  to  allow  for  the  precipitation  of  0.061  gm.  of  calcium  bicarbonate 
per  liter  of  salt  solution  when  the  sodium  chloride  in  solution  increases 
from  39.62  to  267.60  gm.  per  liter.  A  nearly  equal  amount,  or  0.04  gm. 
of  bicarbonate  remains  in  solution.  The  general  nature  of  the  problem 
is  similar  to  that  of  the  precipitation  of  gypsum  by  salt,  mentioned 
above.  It  requires  the  previous  solution  of  calcium  bicarbonate  by 
rather  strong  salt  solutions.  Although  the  amount  of  limestone  that 
would  be  precipitated  by  this  process  is  small,  it  could  build  up  thick 

11  Econ.  Geol  (1918)  13,  619.  Reference  to  Cameron  and  Seidell,  U.  S.  Dept.  of 
Agric.,  Div.  of  Soils,  Bull  18,  58-64;  also  Jnl.  Phys.  Chem.  (1901)  6,  643. 


276  OIL-FIELD  BRINES 

limestone  caps  in  geological  time,  if  the  salt  solutions  penetrated  far 
enough  through  the  sediments  to  gather  nearly  twice  the  required  amount 
of  bicarbonate. 

In  other  words,  all  present  theories  of  the  secondary  chemical  origin 
of  the  substances  in  salt  cores  require  extensive  circulation.  Extensive 
circulation,  by  releasing  artesian  waters,  must  promote  solution  rather 
than  precipitation  of  salt.  The  gypsum  and  limestone  may  be  precipi- 
tated in  situ.  The  salt  must  be  intrusive  en  masse. 

SOLUTION  AND  DEPOSITION  OF  LIME  IN  SANDS 

Messrs.  Mills  and  Wells'2  describe  processes  by  which  calcium  car- 
bonate is  deposited  in  the  sands.  They  show  that  this  may  result  either 
from  the  mingling  of  waters  containing  calcium  chloride  with  waters 
containing  alkaline  carbonates,  or  through  the  liberation  of  carbon  diox- 
ide from  the  waters.  The  deposition  of  lime  carbonates  probably 
explains  the  occurrence  of  the  numerous  non-productive  or  slightly  pro- 
ductive areas  that  occur  in  all  highly  calcareous  oil  sands.  It  is  probably 
also  the  explanation  of  the  presence  of  cap  rocks  on  the  tops  of  pay  sands. 
Nearly  all  drillers  believe  that  there  is  a  hard  streak,  or  cap  rock,  along 
the  top  of  nearly  all  productive  oil  sands.  This  belief  is  so  universal 
that  it  must  be  based  on  fact,  but  the  origin  of  the  cap  rock  remains  to 
be  explained.  The  writer  is  unable  to  advance  any  reason  why  lime 
cement  should  be  deposited  between  the  sand  grains  along  the  tops  of 
the  sands  or  in  the  immediately  adjacent  base  of  the  overlying  shale. 

Calcareous  sands,  commonly,  are  firm  hard  rocks  at  the  outcrop,  but 
most  oil  sands  in  Oklahoma,  California,  and  the  Appalachian  fields 
appear  to  be  much  softer  and  more  easily  drilled  than  the  water-bearing 
parts  of  the  sand  or  the  cap  rock.  The  writer  has  regarded  this  as  at 
least  an  indication  that  the  carbonate  cement  had  been  dissolved  out  by 
circulating  water  previous  to  or  during  the  time  of  concentration  of  the 
oil  in  the  sand.  The  effect  may  be  due  also  to  the  deposition  of  carbonate 
in  parts  of  the  sand  near  the  outcrop  and  in  parts  of  the  sand  remote 
from  production. 

Further  evidence  of  the  solution  of  calcareous  matter  in  oil  sands  is 
furnished  by  the  general  absence  of  fossil  shells  from  these  sands.  It  is 
often  observed  that  fossil  shells  are  absent  in  the  outcrops  of  oil-saturated 
sands,  although  casts  of  fossils  may  be  common.  Hoefer  has  recorded 
this  same  fact  as  characteristic  of  all  oil  regions.  Fossil  shells  appear 
to  be  found  in  the  outcrops  of  oil-saturated  sands  only  where  the  sand 
consists  mainly  of  calcareous  material.  In  these  cases  there  was  prob- 
ably more  calcite  present  than  the  solution  could  remove.  The  only  ex- 
planation of  this  solution  of  calcite  that  the  writer  has  observed  in 

"  U.  8.  Geol.  Survey  Bull.  693  (1919)  50,  100. 


CHESTER   W.    WASHBURNE  277 

previous  literature  is  Hoefer's  hypothesis  that  the  carbonate  is  dissolved 
by  the  waters  associated  with  the  oil  because  of  the  liberation  of  carbon 
dioxide  formed  by  slight  oxidation  of  the  oil,  possibly  aided  by  solution 
in  the  organic  acids  that  exist  in  traces  in  many  oils. 

This  explanation  does  not  appear  to  be  wholly  adequate.  The  reac- 
tions given  by  Mills  and  Wells13  for  the  hydrolysis  of  magnesium  car- 
bonate and  magnesium  chloride,  resulting  in  the  formation  of  free  car* 
bon  dioxide  and  hydrochloric  acid,  would  explain  the  solution  of  calcium 
carbonate  very  readily,  as  shown  by  the  following  equations: 

MgC03  +  H20      =  Mg(OH)2  +  C02 
CaC03  +  H2C03  =  CaH2(C03)2 
Also, 

MgCl2  +  2H20  =  Mg(OH)2  +  2HC1 
CaC03  +  2HC1  =  CaCl2  +  C02  +  H20. 

Both  of  these  reactions  probably  would  result  in  the  deposition  of 
magnesium  carbonate  in  the  place  of  the  dissolved  calcium  carbonate, 
but  Messrs.  Mills  and  Wells  cite  an  example  in  which  crusts  of  calcium 
carbonate  were  dissolved  from  the  water  jackets  of  gas  engines  by  pump- 
ing brines  rich  in  magnesium  chloride  through  the  jackets.  The  reactions 
take  place  readily  in  warm  solutions  and  they  probably  operate  very 
slowly  in  cold  solutions. 

There  is  a  translation  or  diffusion  of  dissolved  calcium  carbonate 
through  the  water  in  an  oil  sand,  from  points  of  solution  to  points  of 
deposition.  As  long  as  the  water  is  in  contact  with  calcium  carbonate, 
it  must  be  nearly  saturated  with  that  substance.  It  is  probably  capable 
of  dissolving  small  particles  of  calcite  and  of  depositing  the  dissolved 
carbonate  on  larger  masses,  as  in  the  process  of  laboratory  "digestion" 
to  increase  the  size  of  precipitated  crystals.  This  appears  to  be  the  main 
cause  of  the  growth  of  concretions  in  shale  and  sandstone.  That  the 
process  may  be  extensive  is  proved  by  the  abundance  of  concretions  in 
many  formations,  including  shales  that  appear  almost  impervious.  The 
magnitude  of  the  process  is  demonstrated  also  by  the  occurrence  of  great 
concretionary  masses,  scores  of  feet  across,  found  in  some  of  our  western 
formations.  These  must  have  drawn  their  supply  of  carbonates  from 
considerable  distances.  The  transfer  of  carbonate  through  sands  may 
be  due  either  to  the  movement  of  the  water  or  to  the  diffusion  of  dis- 
solved^carbonates  and  bicarbonates  through  the  water,  or  to  both  proc- 
esses combined. 

The  solution  of  calcium  carbonate  would  be  promoted  by  the  presence 
of  magnesium  chloride,  as  shown  by  Mills  and  Wells,  and  magnesium 
would  be  exchanged  for  calcium  in  solution.  The  formation  of  dolomite 
in  this  way  has  long  been  regarded  as  a  cause  of  the  porosity  of  the  oil 

"  U.  S.  Geol.  Survey  Bull.  603  (1919)  72. 


278  OIL-FIELD   BRINES 

pay  of  the  Trenton  limestone  of  Ohio  and  of  the  Corniferous  limestone 
of  the  Irvine  field,  Kentucky.  Bownocker  has  demonstrated  that  the 
percentage  of  magnesium  in  the  Trenton  limestone  increases  as  one 
approaches  an  oil  field,  and  that  it  reaches  a  maximum  in  the  productive 
area.  The  writer  has  observed  that  the  limestone  adjacent  to  oil-filled 
crevices  in  the  outcrop  of  the  Tamosopo  limestone  of  the  Sierra  Madre 
Oriental,  Mexico,  is  dolomitic,  although  the  rest  of  the  limestone,  begin- 
ning a  few  inches  away  from  the  crevices,  was  practically  pure  calcium 
carbonate.  This  indicates  that  the  original  waters  in  oil  fields  were  rich 
in  magnesium  and  that  the  magnesium  had  been  lost  from  solution  by 
the  replacement  of  calcium  in  solid  carbonates. 

This  process  does  not  explain  all  of  the  features  of  solution.  Some 
fragments  of  the  Corniferous  limestone  blown  out  of  wells  in  the  Irvine 
field,  Kentucky,  contain  solution  cavities  an  inch  or  more  across.  The 
same  is  true  of  the  cap  rocks  of  the  Gulf  Coast  oil  fields.  The  presence 
of  these  large  cavities  in  solid  limestone  demonstrates  that  underground 
waters  have  dissolved  much  calcium  carbonate  besides  that  replaced  as 
dolomite.  It  would  be  of  great  interest  to  students  of  oil  geology  if 
Messrs.  Mills  and  Wells  would  devote  attention  to  this  subject  of  solu- 
tion of  calcareous  cement. 

In  certain  oil  fields  the  process  of  solution  has  been  very  extensive. 
Some  of  the  oil  sands  of  California  which  are  hard  calcareous  sands  at 
their  outcrops  are  only  loose,  friable,  unconsolidated  sands  in  the  pay 
parts  underground.  The  same  is  true  of  the  Woodbine  sand  of  Louisiana 
and  of  many  other  sands.  Frequently  these  sands  are  so  loose  that  they 
will  flow  into  the  wells  with  the  oil  and  clog  the  holes.  As  a  general 
rule,  nearly  all  oil  sands  are  so  loose  that  sand  grains  work  into  the  valves 
of  the  pumps  and  wear  them  out  within  a  few  months;  this  is  more  rarely 
the  case  with  pumps  that  lift  water.  It  appears  to  the  writer  that  there 
is  a  general  process  of  solution  of  carbonate  cements  in  oil  sands. 

At  the  same  time  there  is  probably  deposition  of  calcium  carbonate 
between  the  sand  grains  along  the  top  of  the  sand  and  in  the  parts  of  the 
sand  that  lie  outside  of  the  productive  areas.  Very  commonly,  the  parts 
of  a  sand  that  lie  structurally  far  below  the  oil-producing  levels  are  so 
tightly  cemented  that  they  appear  dry  to  drillers.  There  seems  to  be 
no  reason  to  doubt  that  these  barren  parts  of  the  sand  are  filled  with 
water,  rather  than  with  oil  or  gas,  and  that  the  water  is  under  pressure 
equivalent  to  that  in  the  productive  areas.  The  only  reason  why  the 
water  does  not  enter  the  wells  in  noticeable  quantities  must  be  because 
the  pores  are  so  fine  and  so  clogged  with  mineral  matter  that  it  will  not 
move  with  sufficient  velocity  into  the  wells  to  be  noticeable.  This  con- 
dition is  true  of  a  broad  area  of  the  Bartlesville  sand  northwest  of  the 
Gushing  oil  field,  Oklahoma.  It  is  true  also  of  most  of  the  synclinal 
areas  surrounding  Ranger,  and  other  fields  of  Eastland  County,  Texas, 


CHESTER   W.    WASHBURNE  279 

but  it  is  not  true  of  the  more  porous  "lime  pays"  of  Stephens  County. 
In  both  the  Gushing  and  Ranger  regions,  the  water  in  the  parts  of  the 
sand  immediately  surrounding  the  productive  areas  will  flow  rapidly  into 
the  well,  but  when  one  gets  a  few  miles  away  from  the  productive  areas 
the  sand  is  so  tight  that  the  drillers  call  it  "dry."  The  natural  inference 
is  that  the  solution  of  lime  cement  in  the  oil-producing  areas  of  a  sand  is 
accompanied  by  the  deposition  of  interstitial  calcite  in  the  non-productive 
regions. 

Some  persons  doubt  that  fine  pores  can  prevent  the  appreciable 
flow  of  water  into  a  well  under  the  pressures  which  exist  at  depths 
of  2000  or  3000  ft.  (609  or  914  m.).  That  this  is  a  fact  they  will 
probably  appreciate  when  they  consider  that  clay  shales  commonly  have 
a  porosity  of  5  to  10  per  cent.,  or  about  half  that  of  the  sands  of  the 
Appalachian  fields.  No  water  is  observed  flowing  into  the  wells  from 
these  shales,  and  it  is  doubtful  if  any  does  enter  except  from  fissures. 
The  main  reason  why  fine  pores  prevent  the  flow  of  water  probably  is 
the  fact  that  there  are  numerous  bubbles  of  gas  scattered  through  the 
pores.  Each  little  bubble  of  gas  is  bordered  by  a  capillary  film  of  water, 
which  clings  to  the  walls  of  the  pores  and  requires  great  pressure  to  move 
it.  If  one  takes  a  fine  capillary  tube  through  which  water  will  flow 
slowly  and  causes  a  few  bubbles  of  air  to  enter,  like  a  string  of  beads,  the 
flow  of  water  will  stop,  even  though  a  much  higher  pressure  is  applied. 
This  is  the  main  reason  why  shales  are  capable  of  sealing  deposits  of  gas 
and  oil.  If  the  pores  of  the  shale  were  not  filled  with  water,  cfpillary 
action  would  quickly  draw  all  of  the  oil  out  of  the  sand  into  the  shale. 
Through  capillary  action  and  through  the  principle  of  the  diffusion  of 
water  vapor  into  shale  described  above,  all  clay  shales  must  be  full  of 
water.  Migration  of  oil  and  gas  across  them  can  be  only  through 
fissures. 

INDUCED  SEGREGATION  OF  OIL  ABOVE  WATER 

M.  J.  Munn  and  Roswell  H.  Johnson  independently  have  shown  that 
there  will  be  no  gravitative  rearrangement  or  stratification  of  oil  above 
water  in  a  sand  that  contains  water  above  oil,  or  in  a  sand  containing  a 
mixture  of  water  and  oil,  unless  the  sand  is  shaken  or  unless  movements 
of  some  kind  are  set  up  in  the  sand  by  external  action.  Recent  experi- 
ments by  McCoy  strengthen  this  conclusion.  Messrs.  Mills  and  Wells14 
have  shown  that  an  induced  segregation  of  this  kind  takes  place  when  a 
mixture  of  oil  and  water  flows  through  an  oil  sand  into  a  well.  As 
thought  by  Johnson,  it  is  quite  probable  that  the  underground  circulation 
of  waters  may  promote  this  segregation  of  oil  and  gas  above  the  water 
in  productive  sands. 

14  U.  S.  Geol.  Survey  Bull  693  (1919)  94,  95. 


280  OIL-FIELD  BRINES 

This  segregation  promotes  the  anticlinal  accumulation  of  oil.  The 
process  may  be  accelerated  by  leakage  upward  across  the  shale  on  the 
tops  of  anticlines.  In  many  fields  there  is  little  indication  of  this  leakage 
along  the  crests  of  anticlines,  and  if  it  occurs  the  oil  probably  is  too  widely 
scattered  in  minute  joints  to  be  noticed  in  drilling.  In  sharply  folded 
regions,  such  as  the  Rocky  Mountains,  oil  seeps  are  common  on  the  axes 
of  anticlines.  In  these  regions,  as  in  the  Salt  Creek  and  Grass  Creek 
fields  of  Wyoming,  one  finds  many  shows  of  oil  in  drilling  through  the 
shale,  and  frequently  there  is  sufficient  oil  in  the  shale  crevices  to  make 
commercial  wells.  In  such  fields  there  is  no  accumulation  of  gas  along 
the  tops  of  the  anticlines.  Many  volumes  of  gas  must  be  formed  for 
each  volume  of  original  oil;  hence,  all  of  the  gas  and  some  of  the  oil  has 
leaked  out  of  the  productive  sands.  Some  of  the  oil  accumulated  in 
higher  sands,  as  in  the  Shannon  sand  of  Wyoming;  some  of  it  is  scattered 
through  small  fissures  in  the  shale;  some  of  it  reached  the  surface  of  the 
ground.  The  paraffine  wax  and  tar  found  along  crevices  at  the  ground 
surface  of  the  Salt  Creek  field  probably  is  the  residue  of  oil  that  has 
leaked  up  from  the  Wall  Creek  sand. 

Oil-field  anticlines  appear  to  be  the  result,  mainly,  of  direct  uplift 
from  the  folding  of  stronger  formations  that  lie  at  greater  depths.  Evi- 
dently there  must  be  much  fracturing  along  their  crests.  The  series  of 
numerous  small  faults  that  cut  across  the  axes  of  Rocky  Mountain  anti- 
clines and  die  out  on  their  limbs  is  an  indication  of  the  type  of  fissures 
through  which  most  of  the  upward  migration  or  leakage  has  occurred. 
Most  of  the  accumulation  occurs  in  the  first  sands  above  the  source  of 
oil.  The  accumulation  in  higher  sands  is  in  smaller  quantity  and  the 
oil  generally  has  become  heavier  because  of  the  oxidation  it  has  suffered 
en  route.  This  upward  leakage  along  the  tops  of  the  folds  may  have 
been  more  extensive  than  commonly  thought.  It  would  cause  circula- 
tion, thereby  promoting  the  gravitative  segregation  of  oil  above  water 
in  the  sands,  in  a  manner  similar  to  that  which  Messrs.  Mills  and  Wells 
have  observed  in  producing  oil  wells. 

SUMMARY  * 

The  concentration  of  the  brines  in  deep  wells  probably  results  in  part 
from  evaporation  in  gas  that  ascends  through  fissures  or  that  comes  in 
contact  with  the  deep  water  in  any  way. 

Water  vapor,  also,  is  transferred  from  sand  to  shale  by  diffusion, 
when  the  sand  is  partly  filled  with  gas.  The  water  vapor  is  evaporated 
from  the  broadly  concave  water  surfaces  in  sands,  and  precipitated  on 
the  relatively  sharply  concave  surfaces  in  shale.  This  process  also  con- 
centrates the  water  solutions  in  the  sands. 


DISCUSSION  281 

The  salt  cores  of  the  Gulf  Coast  could  not  have  been  formed  by  the 
precipitation  of  salt  from  solution,  because  they  cut  across  many  sands 
that  outcrop  inland  at  higher  elevations.  Any  upward  movement  of 
water  at  the  site  of  a  salt  core  would  set  up  a  vigorous  artesian  circula- 
tion of  fresh  water  through  these  sands,  which  would  destroy  the  con- 
centration of  the  ascending  solutions  and  would  prevent  the  precipitation 
of  salt.  The  salt  cores  seem  to  be  intrusive  plugs  of  salt. 

The  gypsum  on  top  of  the  salt  plugs  may  be  uplifted  parts  of  deeper 
gypsum  beds,  or  may  be  secondary  precipitates.  The  gypsum  deposits 
in  the  Red  Beds  of  our  Western  States  appear  to  be  primary  precipitates 
in  lakes,  but  some  of  them  show  structural  indications  of  subsequent 
growth  by  the  secondary  precipitation  of  gypsum. 

The  origin  of  the  limestone  caps  of  the  salt  cores  remains  to  be  ex- 
plained. 

Carbonate  cement  has  been  dissolved  from  many  pay  sands,  leaving 
them  softer  and  more  friable  than  neighboring  dry  areas  of  the  same  sand. 
The  solution  is  probably  due  to  the  formation  of  bicarbonates  from  oxida- 
tion of  the  oil  by  sulfates,  etc.  Organic  acids  may  slightly  assist  the 
solution  of  the  cement.  The  entrance  of  brines  containing  magnesium 
chloride  would  cause  solution  of  calcium  carbonate  by  hydrolysis,  as 
shown  by  Mills  and  Wells,  but  part  of  the  calcite  would  be  replaced  by 
dolomite. 

Carbonate  cement  appears  to  be  deposited  along  the  tops  of  oil  sands, 
forming  the  so-called  hard  caps  or  cap  rock  of  drillers.  No  reason  for 
this  action  comes  to  mind. 

DISCUSSION 

R.  VAN  A.  MILLS,*  Washington,  D.  C.  (written  discussion  f). — Mr. 
Washburne's  paper  is  essentially  a  discussion  of  certain  parts  of  a  Geo- 
logical Survey  Bulletin.15  The  problems  under  discussion  are  so  difficult 
to  solve,  and  are  of  such  scientific  interest  and  economic  importance  as 
to  demand  our  continued  efforts  toward  their  study.  It  is  to  be  regretted, 
however,  that  the  author  has  not  presented  more  data  resulting  from  his 
own  investigations.  Real  progress  in  petroleum  geology  at  the  present 
stage  of  its  development  demands  investigative  rather  than  speculative 
study. 

Messrs.  Mills'  and  Wells'  conception  of  the  origin  of  the  brines  asso- 


*  Petroleum  Technologist,  U.  S.  Bureau  of  Mines. 
t  Published  by  permission  of  the  Director  of  the  Bureau  of  Mines. 
15R.  V.  A.  Mills  and  R.  C.  Wells:  Evaporation  and  Concentration  of  Waters 
Associated  with  Petroleum  and  Natural  Gas.     U.  S.  Geol.  Survey  Bull  693  (1919). 


282  OIL-FIELD  BRINES 

elated  with  petroleum  and  natural  gas  in  the  Appalachian  fields  is  sum- 
marized as  follows:16 

Marine  water  of  sedimentation  and  ground  water  from  other  sources  have  been 
included  and  deeply  buried  in  the  sediments,  where,  in  association  with  gas  and 
oil,  they  have  migrated  and  undergone  concentration,  accompanied  by  changes  in 
the  nature  and  relative  proportions  of  the  dissolved  constituents.  Concentration 
is  due  in  part  to  the  leaching  of  the  sediments  by  the  migrating  waters,  but  mainly 
to  the  evaporation  of  water  into  gases  that  are  moving  and  expanding  through  natural 
channels.  Reactions  between  the  dissolved  constituents  of  different  types  of  waters 
and  between  the  dissolved  constituents  of  the  waters  and  the  organic  and  inorganic 
constituents  of  the  sediments,  have  been  important  factors  in  the  formation  of  the 
brines,  and  so  also  have  mass  action  and  reactions  due  to  deep-seated  thermal 
conditions. 

The  fact  is  emphasized  that  deep-seated  evaporation  is  only  one  of 
many  factors  entering  into  the  formation  of  the  brines.  The  factors 
governing  the  formation  of  the  Appalachian  brines  cannot  be  the  same  as 
those  giving  rise  to  the  primary  alkaline  waters  of  certain  California 
fields  or  the  sulfate-bearing  brines  of  Wyoming,  Kansas,  and  Oklahoma. 
Generalizations  upon  the  formation  of  oil-field  brines  should  follow 
rather  than  precede  intensive  studies  in  different  fields. 

The  diffusion  of  water  vapor  through  natural  gas  as  an  attribute  to 
the  deep-seated  evaporation  and  concentration  of  the  brines  has  also  been 
considered.17  Mr.  Washburne's  hypothesis  upon  the  condensation  of  this 
diffused  water  vapor  in  shale  and  the  influence  of  such  a  process  upon  the 
concentration  of  the  brines  remaining  in  the  sands  is  too  speculative  to 
be  accepted  without  substantiative  field  and  laboratory  data. 

The  writers  of  the  Government  Bulletin  pointed  out  that  deep-seated 
concentration  and  precipitation  caused  by  the  evaporation  of  brines  in 
ascending  gases,  together  with  precipitation  by  the  geochemical  proc- 
esses outlined  in  that  paper,  have  probably  played  important  roles  in 
the  formation  of  the  salt  masses  and  associated  cap  rocks.  These  con- 
ceptions hold  true,  no  matter  what  theories  may  be  regarded  as  best 
explaining  the  origin  of  the  domes.  Mr.  Washburne's  selection  of  the 
maximum  volume  of  gas  (at  a  pressure  of  100  atmospheres)  required  to 
cause  the  deposition  of  a  unit  volume  of  salt  by  evaporation  is  some- 
what misleading.  The  fact  is  emphasized  that  as  gas  expands  from  a 
pressure  of  100  atmospheres  to  a  pressure  of  1  atmosphere  (at  constant 
temperature) ,  the  volume  of  the  gas  and  hence  its  capacity  to  carry  mois- 
ture is  increased  a  hundredfold.  A  gradual,  and  possibly  slight,  lowering 
of  temperature  during  the  upward  passage  of  the  gas  would  make  com- 
paratively little  difference  in  the  evaporation  effects  of  the  ascending  gas. 

"Bull.  693,  6.  "Butt.  693,  80. 


DISCUSSION  283 

As  pointed  out18  1  cu.  m.  of  gas  expanding  from  100  atmospheres  to  1 
atmosphere  at  a  constant  temperature  of  40°  C.  would  be  able  to  evaporate 
3800  gm.  of  water  from  a  saturated  solution  of  sodium  chloride,  thus 
causing  the  precipitation  of  1400  gm.  or  658  c.c.  of  salt.  In  this  case  the 
original  volume  of  the  compressed  gas  required  to  cause  the  precipitation 
of  1  cu.  m.  of  salt  at  or  near  the  earth's  surface  would  be  1500  cu.  m.,  but 
at  deep-seated  temperatures  and  pressures,  the  original  volume  of  the 
compressed  gases  required  to  cause  such  a  deposition  of  salt  by  evapora- 
tion would  probably  be  less  than  145  cu.  m.  Should  the  gas  expand  from 
an  initial  pressure  of  200  atmospheres  at  a  temperature  of  100°  C.,  only 
72.5  cu.  m.  of  compressed  gas  would  be  required  to  cause  the  deposition 
of  1  cu.  m.  of  salt.  At  higher  temperatures  the  initial  volume  of  the 
compressed  gas  required  to  accomplish  this  evaporation  would  be  less 
than  72.5  cubic  meters. 

To  avoid  the  misunderstanding  that  may  arise  from  Mr.  Washburne's 
paper,  the  entire  paragraph  from  which  he  takes  his  data  on  the  volume 
of  gas  required  to  cause  the  deposition  of  a  unit  volume  of  salt  is  given:19 

On  the  hypothesis  of  a  cooling  brine,  then,  we  calculate  that  1  cu.  m.  of  saturated 
brine  would  deposit  11  kg.  of  salt  on  cooling  from  60°  to  20°  C.,  whereas  the  same 
amount  of  salt  could  be  deposited  from  such  brine,  through  evaporation,  by  the  es- 
cape of  790  cu.  m.  of  gas  at  40°  C.,  307  cu.  m.  at  60°  C.,  or  74  cu.  m.  at  100°  C.  If  the 
gas  expands  a  hundredfold  at  the  temperatures  mentioned,  the  volumes  of  compressed 
gas  required  would  be  only  about  a  hundredth  of  those  mentioned.  In  short,  the 
volumes  of  compressed  gas  would  have  to  be  from  24  to  260  times  greater  than  a  given 
volume  of  brine  to  leave  salt  as  the  final  product  under  reasonably  favorable  condi- 
tions. The  volumes  of  gas  required  are  145  and  1550  times  the  volume  of  salt  formed 
at  100°  C.,  and  40°  C.,  respectively.  Looked  at  in  another  way,  1  cu.  m.  of  brine  could 
deposit  11  kg.  of  salt  by  cooling  or  330  kg.  by  evaporation. 

Mr.  Washburne's  assumption  that  the  salt  masses  were  formed  at 
temperatures  not  exceeding  40°  C.  is  unjustified.  Also,  his  statement 
that  the  escape  of  the  gas  causing  evaporation  "could  be  only  through 
vertical  channels  which  would  necessarily  be  so  free  and  open  that  there 
could  have  been  no  accumulation  of  oil  and  gas  at  these  places,"  does  not 
accord  with  present  conditions  in  the  salt-dome  region  where  there  are 
today  many  natural  exudations  of  gas  though  the  fields  are  produc- 
tive. In  Washington  and  Morgan  Counties,  Ohio,  gas  is  escaping  from 
sands  only  30  to  100  ft.  beneath  the  surface  where  little,  if  any,  oil 
escapes  except  where  the  oil  sands  are  actually  exposed  at  the  surface. 
Oil  is  being  recovered  from  wells  drilled  to  these  oil  sands  only  a  few 
hundred  feet  from  their  outcrops  and  at  similar  distances  from  the  places 
where  the  gases  are  escaping. 


i*Bull  693,  84.  "  Bull.  693,  92-93. 


284  OIL-FIELD  BRINES 

A  concrete  example  of  the  amount  of  salt  that  may  be  deposited 
through  the  evaporative  effects  of  expanding  gas  is  given  in  the  Govern- 
ment Bulletin.  In  a  gas  well  that  was  "shut  in"  but  in  which  there  was 
underground  leakage  of  both  salt  water  and  gas,  more  than  two  tons  of 
salt  were  deposited  during  four  months.  The  well  cavity  was  filled  with 
salt  to  a  height  of  several  hundred  feet  from  the  bottom. 

Mr.  Washburne's  generalizations  upon  the  effects  of  fresh  water  in 
the  strata  surrounding  the  salt  domes  do  not  seem  to  be  warranted  be- 
cause there  is  no  certainty  as  to  how  long  these  conditions  have  prevailed. 
They  may  not  have  existed  when  the  domes  were  formed;  also  it  is  a 
matter  of  speculation  as  to  whether  the  water  conditions  outlined  are  at 
all  general.  The  subject  requires  intensive  field  and  analytical  study  in 
conjunction  with  deep  drilling. 

In  outlining  the  various  theories  advanced  to  explain  the  origin  of 
the  salt  domes,  the  authors  of  the  Government  Bulletin  say: 

Several  European  geologists  have  recently  revived  the  old  and  long-neglected  view 
that  salt-dome  structure  is  due  to  the  flow  of  salt  made  plastic  by  pressure.20  Lach- 
mansl  calls  attention  to  the  variety  of  deformations  found  in  the  German  salt  deposits 
and  shows  that  the  structural  features  range  from  those  that  are  entirely  conformable 
to  the  strata  in  which  the  salt  deposits  are  found  to  those  of  domes  which  show  prac- 
tically no  relation  to  the  adjoining  strata,  having  apparently  been  formed  by  the 
flowage  of  salt.  Arrhenius 22  has  discussed  some  of  the  physical  and  chemical  problems 
involved  in  the  formation  of  the  German  salt  deposits  and  applies  the  principles  of 
isostasy  to  explain  the  salt  column  in  Drake's  Saline,  Louisiana.  Before  this  ex- 
planation can  be  accepted,  experiments  upon  the  plastic  flow  of  salt,  with  special 
reference  to  the  effect  of  temperature  and  pressure,  the  action  of  water,  and  the  pos- 
sibility of  flow  by  fracturing  and  granulation,  followed  by  recementation  and  re- 
crystallization  are  needed.  Inasmuch  as  Arrhenius  assumes  that  solutions  have  acted 
to  some  extent  as  a  lubricant  for  the  movement  of  the  salt,  and  also  that  many  of  the 
unusual  structural  forms  found  in  the  German  potash  salts  are  due  to  rearrangements 
brought  about  by  water  given  off  from  hydrated  minerals  at  depth,  we  feel  that,  even 
if  the  preceding  views  are  accepted,  the  evaporation  of  solutions  by  gases  is  worthy 
of  consideration. 

Conditions  of  comparative  weakness  that  might  permit  the  plastic  flow  of  salt 
under  great  pressure  would  also  permit  the  movement  and  probably  the  escape  of  solu- 
tions and  gases,  especially  where  the  movements  of  salt  were  accompanied  by  faulting 
and  fracturing  of  the  overlying  strata.  Probably  no  one  of  the  theories  we  have  cited 

*°  O.  Grape :  Zechsteinf ormation  und  ihr  Salzlager  im  Untergrunde  des  hannover- 
schen  Eichsfelds:  Zett.  praK.  Geol.  (1909)  17,  185.  E.  Harbort:  Geologic  der 
nordhannoverschen  Salzhorste:  Deutsch.  geol.Gesell.  Monatsber.  (1910),  326;  Richard 
Lachmann:  Salinare  Spalteneruption  gegen  Eksemtheorie :  Idem,  697;  H.  Stille: 
Aufsteigen  des  Salzgebirges:  Zeit.  prak.  Geol.  (1911)  19,  91. 

11  Richard  Lachmann:  Der  Salzauftrieb,  Halle,  1911.  Separate  from  Kali. 
(1910)  4,  Nos.  8,  9,  22,  23  and  24.  Studien  ueber  den  Bau  von  Salzmassen:  Idem. 
(1913)  6,  pp.  342-353,  366-375,  397-401,  418-431. 

18  Arrhenius,  Svante,  Zur  Physik  der  Salzlagerstatten:  Meddelandenk.v.  Nobel- 
institut  (1912)  2,  No.  20. 


DISCUSSION  285 

will  suffice  to  explain  all  the  unusual  phenomena  of  salt  domes,  but  it  is  evident  that 
in  conjunction  with  any  of  the  processes  mentioned  the  evaporation  of  water  into 
moving  and  expanding  gas  must  be  regarded  as  important. 

In  the  light  of  present  information,  the  origin  of  the  cap  rocks,  gyp- 
sum and  limestone,  may  well  be  regarded  as  geochemical,  according  to  the 
principles  cited  by  Mills  and  Wells23  and  by  DeGolyer.24  A  geochemical 
theory  for  the  origin  of  the  cap  rocks  may  also  furnish  an  explanation 
for  the  failure  of  fresh  waters  to  dissolve  the  salt  masses.  Salt  deposits 
in  oil  and  gas  wells  are  frequently  covered  and  protected  against  solution 
by  calcium  carbonate  and  calcium  sulfate  precipitated  by  infiltrating 
fresh  waters.  The  introduction  of  primary  alkaline  and  sulfate-bearing 
waters  into  wells  to  dissolve  salt  frequently  fails  to  accomplish  this  pur- 
pose. Sometimes  the  reactions  are  such  as  to  contribute  more  salt  to 
that  already  in  the  wells,  as  in  the  reaction: 

2  NaHC03  +  CaCl2  =  CaC03  +  2  NaCl  +  C02  +  H20 

If  the  solutions  are  not  saturated  with  sodium  chloride,  the  calcium  car- 
bonate around  deposited  salt  protects  it  against  solution.  These  princi- 
ples may  well  apply  to  the  cap-rock  phase  of  the  salt-dome  problem. 

The  writer  cannot  agree  with  Mr.  Washburne's  generalization  that  the 
tightly  cemented  sands  along  the  tops  and  bottoms  of  productive  sands 
are  characteristically  calcareous.  The  examination  of  several  hundred 
samples  of  pay  sands  and  their  associated  rocks  of  Pennsylvanian,  Missis- 
sippian,  and  Devonian  ages  in  Ohio,  Pennsylvania,  and  West  Virginia 
has  shown  the  breaks  and  caps  of  pay  sands  to  be  characteristically 
quartzitic  and  lacking  in  lime.  In  samples  of  sandstone  and  shale  for- 
mations from  deep  wells  in  those  fields,  most  of  the  calcium  carbonate 
found  appears  to  have  been  deposited  through  induced  cementation  sub- 
sequent to  the  drilling  and  operation  of  wells.  The  analysis  of  oil-  and 
gas-bearing  sands  and  their  associated  rocks  and  the  discussion  of  deep- 
seated  waters  as  agents  of  cementation  and  of  induced  cementation26 
should  make  these  points  clear  so  far  as  the  fields  examined  for  that 
report  are  concerned.  The  original  lime  content  of  the  deep-seated  sands 
and  shales  has  evidently  gone  into  solution  as  chloride  and  bicarbonate. 

While  engaged  in  field  work,  during  the  preparation  of  Bull.  693,  the 
writer  observed  that  the  sandstones  exposed  to  salt  waters  pumped  from 
old  oil  wells  in  Butler  County,  Pennsylvania,  were  being  disintegrated 
and  rendered  more  porous  and  friable  by  leaching  and  etching. 
Lumps  of  sandstone,  the  size  of  a  man's  fist,  from  the  paths  of  the  salt 
waters  trickling  from  the  tanks  around  these  wells,  could  be  crushed 
when  slightly  squeezed  in  the  hand.  The  waters  not  only  dissolved  the 
cementing  material  but  etched  the  quartz  grains.  The  fact  that 
oil-field  waters  are  agents  for  the  solution  as  well  as  the  deposition  of 

23  Bull.  693.  "Econ.  Geol  (1918)  13.         ™  Bull.  693,  16-18,  76,  44-50,  98. 


286  OIL-FIELD  BRINES 

mineral  matter  is  thoroughly  established  but,  except  for  the  work  of 
Chase  Palmer,  the  geochemistry  of  some  of  the  processes  involved  has 
yet  to  be  made  clear. 

In  regard  to  the  unconsolidated  sands  of  the  California  fields,  has  not 
Mr.  Washburne  put  the  cart  before  the  horse?  That  sands  at  their  out- 
crops have  been  cemented  through  surface  agencies  in  no  way  signifies 
that  the  beds  were  ever  similarly  cemented  at  depth. 

Recent  experiments26  made  by  the  writer  tend  to  disprove  Mr.  Wash- 
burne;s  opinion  that  oil  does  not  segregate  "gravitationally  "  above  water 
under  hydrostatic  conditions  in  sands.  Such  segregation  occurs  very 
readily  with  certain  oils  and  brines,  even  in  sands  of  extremely  fine  texture. 
It  is  recognized,  however,  that  where  the  segregation  of  oil  above  water  is 
incomplete,  currents  induced  by  the  drilling  and  operation  of  wells  may 
cause  the  oil  to  migrate  and  to  segregate  more  completely  above  the 
water;  it  is  this  that  the  writer  has  termed  induced  segregation. 

The  principles  of  induced  segregation  are  worthy  of  consideration 
in  the  practical  recovery  of  oil  and  gas  as  well  as  in  the  study  of  oil  and 
gas  accumulation.  It  seems  probable  that  favorably  situated  parts  of 
pay  sands  are  enriched  by  induced  migration  and  segregation.  Again, 
the  escape  of  gases,  oils,  and  waters  through  natural  passages  such  as 
fissures  has  evidently  caused  the  migration  and  accumulation  of  the  re- 
maining hydrocarbons  into  favorable  entrapments.27  Some  of  the  ac- 
cumulations associated  with  faults  have  evidently  originated  in  this  way. 
Apparently  Mr.  Washburne  accepts  these  views  as  he  repeats  them  in 
his  paper. 

R.  VAN  A.  MILLS  (oral  discussion). — The  investigation  outlined  in 
U.  S.  Geol.  Survey  Bull.  693  was  based  largely  on  studies  of  the  changes 
in  Appalachian  oil-field  waters  incident  to  the  drilling  and  operation  of 
wells.  One  of  the  principal  changes  is  concentration  due  to  the  evapo- 
ration of  the  brines  in  expanding  gas,  the  brines  becoming  sufficiently  con- 
centrated to  cause  the  precipitation  of  a  part  of  their  dissolved  mineral 
matter.  Realizing  that  the  mineral  deposits  in  wells  could  not  be  formed 
without  changes  in  the  proportions  of  the  dissolved  constituents  in  the 
waters  that  contributed  the  deposits,  the  next  step  was  to  determine  the 
character  of  these  changes.  It  was  found  that  the  changes  occurred 
through  chemical  reaction  as  well  as  through  concentration.  The  loss 
of  sodium  chloride  is  not  the  only  change;  various  dissolved  constituents 
are  lost  from  solution,  the  changes  are  complex,  many  factors  being 
involved. 

I  regard  the  hypothesis  that  diffused  water  vapor  is  condensed  in  the 
shales  as  rather  speculative.  More  data  are  needed  to  establish  such  a 
theory. 

As  to  the  salt-dome  problem;  it  was  far  from  the  intention  of  the 

*•  Econ.  Geol.  (1920)  15,  39&-421.  r  Butt.  693,  94-95. 


DISCUSSION  287 

authors  of  the  Government  bulletin  to  attribute  the  formation  of  the 
salt  domes  entirely  to  evaporation.  We  must  attack  this  problem  upon 
a  basis  of  the  multiple  hypothesis,  without  restricting  ourselves  to  any 
one  theory.  I  believe  that  the  theory  of  the  deposition  of  salt  due  to 
the  evaporation  of  brines  by  expanding  gases  is  one  of  the  theories 
worthy  of  consideration. 

At  present  there  is  a  considerable  natural  escape  of  gas  in  the  salt- 
dome  region  where  oil  is  being  produced;  consequently,  Mr.  Washburne's 
statement  that  the  oil  would  have  escaped  with  the  gas  causing  the 
evaporation  is  not  upheld  by  present  conditions.  In  many  fields  where 
we  now  have  production,  we  also  have  the  natural  escape  of  gas.  In 
Morgan  and  Washington  Counties,  Ohio,  within  a  few  hundred  feet  of 
gas  exudations,  we  have  good  oil  production  in  the  sands  from  which  the 
gas  is  escaping.  We  also  have  good  oil  production  within  similar  dis- 
tances of  the  outcrops  of  the  oil-bearing  sands.  In  one  case,  where  an 
operator  has  installed  a  barrel  which  catches  oil  (3  qt.  in  5  hr.)  from  an 
outcrop  of  the  Cow  Run  sand,  he  is  also  producing  oil  from  wells  tapping 
the  same  sand  400  or  500  ft.  away  from  that  outcrop. 

The  origin  of  the  cap  rocks  overlying  the  salt  masses  appears,  to  me, 
to  be  distinctly  geochemical.  In  various  parts  of  the  Appalachian  field, 
waters  from  shallow  beds,  leaking  into  oil  wells  and  coming  into  contact 
with  deep-seated  brines,  cause  the  deposition  of  mineral  matter  not  un- 
like that  of  the  cap  rocks  of  the  salt  domes.  Thus  in  the  mineral  crusts 
formed  in  oil  wells,  we  frequently  have  calcium  carbonate  and  calcium 
sulfate  associated  with  salt.  Salt  is  occasionally  coated  with  calcium  car- 
bonate and  calcium  sulfate.  Under  these  conditions  the  dissolving  of  the 
salt  might  produce  pores  similar  to  those  in  the  cap  rocks  of  the  domes. 
The  failure  to  remove  salt,  by  introducing  fresh  water  into  "salted-up" 
wells,  is  frequently  due  to  the  reactions  between  the  dissolved  constituents 
of  the  deep-seated  brines  and  those  of  the  fresh  water  introduced  into  the 
wells.  The  water  introduced  into  the  wells  may  not  only  cause  the  pre- 
cipitation of  carbonates  and  sulfates,  but  may  also  cause  the  formation 
of  more  sodium  chloride  according  to  the  reactions  quoted  in  Bull.  693. 

I  wish  to  emphasize  the  advisability  of  avoiding  generalizations  in 
attacking  these  problems.  For  instance,  it  is  erroneous  to  assume  that 
all  of  the  relatively  impermeable  caps  overlying  oil  pays  are  calcareous. 
Several  hundred  samples  of  oil-bearing  sands  and  their  associated  rocks 
in  the  Appalachian  fields  have  been  found  to  be  characteristically  siliceous ; 
carbonates  are  for  the  most  part  absent,  even  in  the  caps  and  breaks, 
except  where  the  sands  were  very  shallow  or  where  they  had  undergone 
induced  cementation  subsequent  to  the  drilling  and  operation  of  wells. 

E.  DEGOLYER,  New  York,  N.  Y. — As  I  understand  it,  Mr.  Wash- 
burne  objects  to  Mr.  Mills'  theory,  and  Mr.  Mills  agrees  with  Mr.  Wash- 


288  OIL-FIELD  BRINES 

burne,  yet  he  answers  rather  extensively  Mr.  Washburne's  arguments. 
I  would  like  to  know  to  what  extent  Mr.  Mills  proposes  his  theory  to 
account  for  the  salt  masses. 

R.  VAN  A.  MILLS. — The  evaporation  theory  is  advanced  simply  to 
supply  one  of  the  factors  entering  into  the  formation  of  the  salt  domes. 
The  last  paragraph  of  the  discussion  of  the  salt-dome  problem28  reads  as 
follows:  " Conditions  of  comparative  weakness  that  might  permit  the 
plastic  flow  of  salt  under  great  pressure  would  also  permit  the  movement 
and  probably  the  escape  of  solutions  and  gases,  especially  where  the  move- 
ments of  salt  were  accompanied  by  faulting  and  fracturing  of  the  over- 
lying strata.  Probably  no  one  of  the  theories  we  have  cited  will  suffice 
to  explain  all  the  unusual  phenomena  of  salt  domes,  but  it  is  evident  that 
in  conjunction  with  any  of  the  processes  mentioned  the  evaporation  of 
water  into  moving  and  expanding  gas  must  be  regarded  as  important." 
In  the  introduction  we  say  that  evaporation  has  played  a  large  part  in 
the  formation  of  the  domes,  but  we  do  not  say  that  this  one  theory  fully 
explains  their  formation. 

E.  DEGOLYER. — Mr.  Washburne  has  objected  to  all  theories  of  the 
precipitation  of  salt  from  solution  by  pointing  out  that  the  salt  plugs 
cut  through  various  sand  strata;  and  by  inference,  if  the  salt  was  deposited 
from  solution,  the  solution  should  have  saturated  these  porous  strata, 
deposition  of  salt  would  have  occurred  and  the  sands  also  should  have 
been  filled  with  salt.  I  think  the  point  is  well  made,  and  the  objection 
seems  to  me  to  be  valid  against  theories  of  deposition. 

R.  VAN  A.  MILLS. — I  do  not  remember  that  these  points  were  raised 
in  the  paper  under  discussion.  Several  years  ago  Mr.  Washburne  sug- 
gested the  hypothesis  of  concentration  of  oil-field  brines  by  evaporation 
into  ascending  gases.  One  of  his  principal  reasons  for  rejecting  that 
hypotheses  was  the  supposition  that  the  interstices  in  the  porous  strata 
would  be  plugged  by  the  deposition  of  salt  incident  to  the  concentra- 
tion. Now  that  has  not  proved  to  be  the  case.  If  the  salt  solutions 
associated  with  oil  and  gas  become  concentrated  sufficiently  to  deposit 
tons  of  salt  in  individual  gas  wells  before  the  water-bearing  strata  are 
sealed,  I  think  we  have  Mr.  DeGolyer's  objections  answered,  in  some 
degree,  by  facts.  The  "salting  up"  of  strata  yielding  unsaturated 
brines  is  a  final  stage  in  the  plugging  process.  I  understand  that  Mr. 
DeGolyer  also  supports  Mr.  Washburne's  objection  to^the  evaporation 
theory  based  upon  the  diluting  and  leaching  effects  of  the  so-called 
"artesian"  waters. 

i  E.  DEGOLYER. — That  was  not  what  I  intended  to  state;  I    was  not 
talking  about  artesian  waters  but  about  the  deposition  of  the  salt  masses 


DISCUSSION  289 

from  any  form  of  solution.  Mr.  Washburne  states  that  we  know  that 
the  salt  masses  pass  through  various  porous  strata  which  are  now  in 
contact  with  the  salt  and  he  contends  that  if  the  salt  was  deposited  from 
solution,  such  solution  would  have  saturated  all  of  the  porous  strata  which 
it  penetrated  and  would  have  deposited  salt  in  them.  If  you  could  get 
salt  masses  deposited  from  solution  in  a  vertical  core  there  would  doubtless 
have  been  motion  of  the  solution  through  the  channel  which  is  now  oc- 
cupied by  the  salt  and  which  penetrates  various  porous  sand  lenses,  thus 
giving  the  solution  access  to  them.  I  am  not  talking  about  the  solu- 
tion moving  through  the  sand,  under  ordinary  conditions,  but  about 
its  moving  into  the  porous  strata  from  such  a  channel. 

R.  VAN  A.  MILLS. — I  cannot  quite  grasp  Mr.  DeGolyer's  point  of 
view.  It  must  be  remembered  that  theories  on  the  deposition  of  salt 
from  solution  embrace  only  a  certain  group  of  the  factors  that  prob- 
ably entered  into  the  formation  of  the  domes.  To  assign  undue  weight 
to  these  contributory  factors  and  then  to  reject  them  altogether  because 
they  fall  short  of  their  assigned  values,  is  erroneous.  It  is  my  impres- 
sion that  fissures  associated  with  the  salt  domes  have  constituted 
channels  for  the  movements  of  solutions  and  gases  toward  the  regions 
of  least  pressure  which  would  be  upward.  New  passages  for  these 
movements  doubtless  have  been  created  as  the  salt  masses  forced*  their 
way  upward  through  the  overlying  strata. 

In  regard  to  the  failure  of  the  shallow  fresh  waters  to  prevent  the 
formation  of  the  salt  masses  or  to  dissolve  away  these  masses  after  they 
were  formed,  it  should  be  remembered  that  when,  in  porous  rocks,  cer- 
tain natural  waters  having  different  properties  of  reaction  come  into 
contact  with  one  another,  chemical  reaction  and  precipitation  frequently 
cause  dense  cementation  along  the  zones  of  contact  between  these  solu- 
tions. Thus  the  fresh  waters  coming  into  contact  with  salt  brines  or  with 
the  salt  masses  may  cause  barriers  to  form,  through  precipitation  and 
cementation,  that  prevent  further  dilution  or  leaching. 

W.  E.  PRATT,*  Houston,  Tex.— Mr.  Washburne  mentions  a  "shell" 
or  hard  upper  crust  on  the  top  of  many  oil-bearing  sands,  for  which 
he  has  no  explanation.  I  understood  Mr.  Mills  to  say  that  he  had  not 
observed  that  condition. 

R.  VAN  A.  MILLS. — In  the  Appalachian  field,  the  shells  and  caps  are 
usually  siliceous  rather  than  calcareous. 

W.  E.  PRATT. — I  am  under  the  impression  that  it  is  a  general  condi- 
tion. Very  often  the  "shell"  is  simply  more  firmly  cemented  with  cal- 
cium carbonate  than  the  lower  part  of  the  same  sands.  I  wanted  to 
ask  whether  other  people's  observations  bore  out  my  impression. 

*  Chief  Geologist,  Humble  Oil  &  Refin.  Co. 

VOL.  UCV. 19. 


290  OIL-FIELD  BRINES 

R.  A.  CONKLING,*  St.  Louis,  Mo. — The  shell  is  usual.  There  may 
be  a  little  poor  sand  almost  on  top  of  the  oil  sand.  In  other  cases,  the 
pay  may  be  almost  at  the  top  of  the  sand.  We  usually  have  cementa- 
tion, but  the  top  part  is  cemented  irregularly. 

R.  VAN  A.  MILLS. — We  have  waters  and  rocks  of  different  types  in 
different  fields.  I  have  accepted  Mr.  Washburne's  paper  as  being  essen- 
tially a  discussion  of  Bull.  693,  which  was  based  on  field  and  laboratory 
work  in  the  Appalachian  field,  and  I  maintain  my  statement  regarding 
the  oil  and  gas-bearing  sands  of  that  region.  In  southeastern  Ohio,  we 
find  the  shallow  pay  sands  carrying  carbonates  which  may  have  been 
formed  partly  through  the  escape  of  gases  and  the  infiltration  of  shallow 
ground  waters  which  would  be  of  the  same  order  as  induced  cementation, 
that  is,  cementation  subsequent  to  the  drilling  and  operation  of  wells. 
The  causes  and  effects  of  induced  cementation  by  carbonates  have  been 
outlined  in  Bull.  693. 

For  the  most  part,  the  caps  and  breaks  in  the  deep-seated  sands  of 
the  Appalachian  fields  are  densely  cemented  sands  and  shales  that  are 
characteristically  siliceous.  Carbonates  are  usually  lacking.  I  think 
most  of  the  carbonates  you  will  find  in  these  deep  sands  are  due  to  induced 

cementation. 

\ 

C.  W.  WASHBURNE  (author's  reply  to  discussion). — It  is  surprising 
to  find  Mr.  Mills  disparaging  speculation,  as  compared  with  investiga- 
tion, because  the  part  of  the  bulletin29  under  review  is  essentially  a  de- 
velopment of  the  idea  of  evaporation  of  oil-field  water  by  underground 
gas,  which  idea  first  appeared  as  a  working  hypothesis  in  a  purely  specu- 
lative study.30  Mills  and  Wells  prove  the  value  of  speculation  by  testing 
this  idea  in  the  field  and  laboratory.  The  new  facts  they  present  will 
lead  many  geologists  to  seek  explanations,  or  to  speculate.  Speculation 
has  nothing  to  do  with  our  daily  work;  yet  it  is  the  mind  and  soul  of 
geology.  Like  all  science,  it  feeds  on  facts. 

Caution  against  over-zealous  application  of  the  idea  of  underground 
evaporation  of  water  is  found  in  the  persistence  of  gasoline  in  crude  oils ; 
it  is  hard  to  evaporate  water  without  evaporating  the  volatile  parts  of 
contiguous  oil.  Practically  all  crude  oils  retain  volatile  components. 
Light  gasoline  is  absent  in  a  few  heavy  crudes,  such  as  the  Topila  and 
Panuco  oils  of  Mexico  and  the  Comodoro  Rivadavia  oil  of  the  Argentine. 
The  lightest  commercial  crude  that  has  no  gasoline  probably  is  that  of 
the  Pine  Island  field,  Louisiana,  which  has  a  specific  gravity  of  about  28° 
Baume".  The  light  oil  of  the  new  Cat  Creek  field,  Montana,  which  has  a 
specific  gravity  of  50°  Baume*,  is  said  to  contain  no  volatile  gasoline, 
such  as  enters  natural  gas,  but  to  have  over  60  per  cent,  of  heavy  gasoline 

*  Head  Geologist,  Roxana  Petroleum  Co. 

»  R.  Van  A.  Mills  and  R.  C.  Wells:  U.  S.  Geol.  Survey  Bull  693  (1919). 

»  C.  W.  Washburae:  Chlorides  in  Oil-field  Waters.     Trans.  (1914)  48,  687. 


DISCUSSION  291 

of  high  initial  boiling  point  but  low  ignition  point,  adapted  to  blending 
with  casing-head  products.  There  is  little  gas  with  the  oil,  which  flows 
from  the  wells  with  a  strange  smoothness,  like  the  oil  in  the  southern 
part  of  the  Peabody  Pool,  Kansas,  and  much  like  artesian  water. 

Gas  probably  accompanies  the  formation  of  all  petroleums.  Where 
it  is  absent,  we  may  infer  that  the  escaping  gas  carried  away  some  of  the 
volatile  constituents;  cases  of  this  kind  are  rare.  Moreover  the  under- 
ground waters  of  these  fields  are  not  very  concentrated;  the  waters  of  the 
gasoline-rich  Appalachian  province  are  much  more  concentrated.  The 
absence  of  gasoline  in  the  rare  exceptions  mentioned  may  be  explained 
by  assuming  that  no  gasoline  occurred  in  the  original  oil,  or  else  that  it 
was  of  types  that  combined  into  heavier  hydrocarbons. 

Evaporation  of  oil  doubtless  is  common  at  shallow  depth,  where  the 
gasoline  content  generally  is  low.  However,  there  is  too  much  gasoline 
in  deep  oils  to  warrant  the  assumption  that  very  much  gas  has  passed 
through  them.  The  deep  oil  sands  contain  the  more  concentrated  brines. 
Hence  the  evaporation  of  water  by  gas  passing  through  it  in  the  oil 
sands  cannot  be  a  very  important  cause  of  its  concentration.  Most  of 
the  concentration  probably  took  place  in  sands  and  other  storage  zones 
far  below  the  present  oil  sands.  The  principles  of  capillarity  and  adsorp- 
tion furnish  good  reasons  for  believing  that  the  pores  of  clay  shales  gener- 
ally are  wet  and  incapable  of  penetration  by  gas  and  oil,  except  under 
unusual  force,  such  as  that  of  deformation.  This  view  is  confirmed  by 
the  geological  preservation  of  gas  and  oil  in  sands  protected  by  shale. 
The  high  temperature  of  great  depth  lowers  the  surface  tension  of  liquids 
and  weakens  all  effects  of  capillarity.  So  far  as  it  goes,  observation  indi- 
cates generally  greater  dryness  in  the  deeper  sands  and  greater  concen- 
tration of  their  brines.  The  exceptions  seem  to  consist  of  continuous 
sands,  such  as  the  Saint  Peter,  that  have  artesian  flow,  which  is  diluted 
with  comparatively  recent  surface  water.  Any  complete  explanation 
should  take  account  of  the  fact  that  Lane  and  others  have  observed 
similar  relations  in  the  deep  mines  of  the  Lake  Superior  and  other  dis- 
tricts, where  water  decreases  with  great  depth  and  becomes  more  con- 
centrated. The  apparent  explanation  is  that  the  concentration  was 
induced  by  evaporation  at  greater  depth  and  that  the  brines  largely  as- 
cended to  their  present  position. 

The  water  in  shale  pores  seals  them  against  penetration  by  gas  and 
oil,  but  does  not  prevent  the  passage  of  water.  Water,  rather  than  gas 
or  oil,  escapes  through  shale  pores.  Vertical  fissures,  if  present,  would 
furnish  the  least  resistance  to  the  escape  of  water,  oil,  or  gas;  they  would 
also  permit  the  ascent  of  gas  and  oil,  which  is  otherwise  impossible, 
except  under  unusual  force.  Hence,  the  settling  and  compacting  of 
strata  by  loading  and  deformation  expels  water,  rather  than  gas.  The 
water  passes  upward  through  the  shale  pores,  at  least  until  it  meets  a 
continuous  sand  through  which  it  can  move  laterally  toward  the  outcrop. 


292  OIL-FIELD  BRINES 

Any  rise  of  temperature,  as  from  deep  burial,  expands  interstitial  gas  and 
forces  more  water  upwards.  The  generation  of  natural  gas  and  oil  must 
displace  water,  driving  it  upwards.  | 

The  following  factor  is  more  hypothetical.  Any  leakage  from  abyssal 
crevices  and  any  "sweating"  through  connecting  pores  would  let  the 
liquids  of  the  earth's  interior  press  upwards  against  the  gas  and  brine 
in  basal  sediments.  Juvenile  water  is  of  recognizable  purity  only  in 
regions  of  marked  diastrophism  or  of  vulcanism,  but  it  seems  improbable 
that  the  rest  of  the  earth  is  so  tight  that  juvenile  gas  and  water  can  not 
filter  very  slowly  into  the  basal  strata  at  many  places.  At  the  tempera- 
tures of  great  depths  viscosity  probably  is  more  important  than  capil- 
larity in  resisting  migration  through  pores.  At  depths  of  a  few  miles, 
such  abyssal  gases  as  helium-rich  nitrogen  and  carbon  dioxides  are  to  be 
expected  to  escape  in  greater  volume  than  water. 

The  ascending  juvenile  liquids  would  mix  with  the  interstitial  liquids 
of  the  sediments  and  would  be  altered  chemically  in  the  new  environ- 
ment. In  the  course  of  geological  time,  they  would  force  all  earth  liquids 
some  distance  upwards,  except  where  the  latter  are  effectively  sealed. 
Thus  in  some  degree  they  add  to  the  ascent  of  rock  brines,  which  are 
driven  upwards  by  the  expansion  of  original  gas  from  heating,  by  the 
generation  of  new  gas  and  oil,  and  by  the  settling  and  compacting  of 
strata  from  loading  and  deformation.  A  part  of  each  brine  is  regarded 
as  connate  with  unknown  deeper  strata,  rather  than  with  the  sand  in 
which  it  now  occurs. 

Mr.  Mills  says:  "Mr.  Washburne's  assumption  that  the  salt  masses 
were  formed  at  temperatures  not  exceeding  40°,  is  unjustified." 
This  figure  was  used  because  it  is  the  lowest  for  which  Mills  and 
Wells  give  the  constants  needed.  It  is  too  high,  at  least  for  the 
probable  temperature  of  the  hypothetical  precipitation  at  the  top  of 
shallow  salt  cores;  admittedly  the  temperature  at  the  bottom  of  the  cores 
was  much  higher.  Many  of  the  salt  masses  reach  the  present  ground  sur- 
face, except  for  a  thin  cover  of  recent  clay.  Most  cores  of  this  type  are 
marked  by  a  semi-circular  lake  or  depression  within  an  enclosing  low 
ridge,  suggesting  that  their  tops  have  suffered  solution.  Many  cores 
are  marked  by  a  low  mound,  due  to  recent  settling  of  the  porous  sedi- 
ments around  the  compact  core,  or  else  to  uplift  of  the  latter.  The 
ridges  encircling  the  lakes  appear  to  be  marginal  remnants  of  collapsed 
mounds,  undermined  by  solution. 

Recent  deposition  has  obliterated  the  surface  manifestation  of  many 
domes.  The  region  of  the  salt  domes  was  characterized  by  an  excess  of 
deposition  over  erosion  throughout  most  of  Tertiary  time,  when  they  were 
formed.  There  is  no  very  great  break  or  hiatus  in  the  record;  every 
Tertiary  epoch  is  represented.  The  formations  are  so  uniform  in  thick- 
ness, distance  considered,  that  we  must  conclude  there  was  no  great  ero- 


DISCUSSION  293 

sion  of  'the  salt-dome  region  in  Tertiary  time.  Deposition  prevailed. 
Post-Tertiary  erosion  is  more  important,  but  both  stratigraphy  and 
physiography  favor  the  idea  that  not  over  100  or  200  ft.  of  cover  had  been 
eroded  from  the  salt  domes  near  the  coast.  Some  of  the  cores  probably 
reached  the  ground  surface,  as  they  do  today;  chemical  deposition  of 
salt  at  the  tops  of  such  cores  would  have  to  take  place  nearly  at  surface 
temperatures.  The  mean  annual  temperature  of  the  region  is  about 
25°  C.  so  that  those  who  favor  the  hypothesis  of  salt  precipitation  must 
admit  that  much  of  the  shallow  precipitation  took  place  at  temperatures 
below  40°  C. 

Mr.  Mills  thinks  it  too  highly  hypothetical  to  assume  that  when  the 
salt  cores  were  formed  the  water  of  the  artesian  sands  was  essentially 
of  the  same  composition  as  today.  What  assumption  could  be  less 
hypothetical?  The  physiographic  and  structural  conditions  of  the  Texas 
coast  have  undergone  little  change  since  that  time.  There  has  been  no 
diastrophism,  other  than  small  epirogenic  movements.  The  salt  cores 
were  formed  in  middle  and  late  Tertiary  time;  the  seacoast  then  lay 
farther  inland,  but  it  did  not  cover  the  outcrops  of  the  Cretaceous  sands, 
nor  even  those  of  the  Wilcox  formation.  These  outcrops  being  on  land 
and  lying  toward  the  source  of  the  sediments,  must  have  been  higher 
than  the  sea,  which  then  covered  some  of  the  coastal  belt.  There  is  no 
hypothesis  involved  in  saying  that  the  Wilcox  sands  under  the  salt  domes 
outcropped  at  a  higher  elevation  inland  at  the  time  the  domes  were 
formed.  The  present  artesian  condition  of  these  sands  is  shown  by  many 
fresh-water  springs  and  wells.  The  same  is  true  of  the  widespread  Trinity 
sand.  The  same  artesian  conditions  must  have  existed  in  these  sands  in 
mid-Tertiary  time,  because  the  character  of  the  sediments  prove  that  they 
were  derived  largely  from  the  northwest  and  were  deposited  on  surfaces 
that  sloped  in  the  same  general  direction  as  the  present  plains.  There  is 
little  hypothesis  involved  in  the  statement  that,  if  these  artesian  sands 
were  punctured  by  fissures  at  the  loci  of  salt  domes  in  mid-Tertiary  or 
later  time,  they  would  let  loose  a  flood  of  fresh  water  that  would  prevent 
precipitation  of  salt.  The  first  water  released  from  a  sand  might  be  very 
salty,  but  a  continuation  of  the  precipitation  of  salt  long  enough  to  pro- 
duce salt  masses  of  several  cubic  miles  surely  would  draw  much  fresh 
water  from  the  higher  inland  parts  of  the  sand.  This  statement  seems 
less  speculative  than  that  of  Mills  and  Wells,  that  expanding  gases 
may  have  concentrated  ascending  brines,  helping  to  precipitate  them  as 
salt  cores.  The  adverse  conditions  seem  too  strong  for  any  theory  of 
precipitation. 

Mr.  Mills'  attempt  to  nullif y  the  dissolving  effect  of  artesian  water  by 
suggesting  that  it  may  have  consisted  of  primary  alkaline  and  sulfate 
water  in  which  common  salt  is  not  very  soluble,  does  not  help  his  case. 
The  climate  of  mid-Tertiary  time  was  less  arid  than  at  present  and  the 


294  OIL-FIELD  BRINES 

ground  water  probably  was  fresher,  otherwise  I  can  see  no  reason  for 
believing  that  its  chemical  nature  was  different.  The  same  formations 
then  surrounded  the  outcrops  of  the  sands.  The  artesian  water  of  the 
Trinity  sand  is  not  characterized  by  high  primary  alkalinity  nor  by  high 
content  of  magnesium  and  calcium  chlorides.  I  can  find  no  analyses  of 
the  water  of  the  Wilcox  sands,  but  I  have  found  it  good  to  drink  in 
many  wells.  Either  water  would  dissolve  common  salt. 

Mr.  Mills  is  quite  right  in  saying  that  my  idea  of  the  vapor  transfer 
of  water  from  sandstone  to  shale  cannot  be  adopted  as  proved  fact. 
Nothing  ever  is  proved;  things  are  established  as  true  only  for  the  time 
that  they  satisfy  knowledge.  I  hope  only  that  this  working  hypothesis 
of  vapor  transfer  will  be  tested,  as  Messrs.  Mills  and  Wells  have  tested 
that  of  underground  evaporation.  Analysis  of  the  forces  exerted  on 
concave  water  films  of  very  sharp  curvature,  as  those  of  capillary  water 
in  shale,  indicates  that  they  promote  condensation  of  water  vapor  to  a 
greater  degree  than  the  relatively  broad  concave  surfaces  of  water  in 
sandstone.  With  reversed  control,  on  account  of  reversed  curvature, 
the  principle  is  essentially  the  same  as  that  of  "digestion"  and  the  pre- 
cipitation of  crystals  in  a  laboratory  beaker,  or  the  growth  of  lime  con- 
cretions with  solution  of  disseminated  calcite  in  rocks  or  the*  growth  of 
raindrops  in  clouds.  The  idea  is  sound  in  theory.  I  believe  the  Bureau 
of  Soils  used  it  as  a  partial  explanation  of  the  transfer  of  soil  water  from 
and  to  clay.  Any  experimental  test  of  the  idea  will  be  appreciated. 


SECONDARY  INTRUSIVE  ORIGIN  OF  GULF  COASTAL  PLAIN  SALT  DOMES      295 


Secondary  Intrusive  Origin  of  Gulf  Coastal  Plain  Salt  Domes 

BY  W.  G.  MATTESON,  E.  M.,  E.  MET.,  FORT  WORTH,  TEX. 

(New  York"  Meeting,  February,  1921) 

THE  origin  of  the  salt  domes  of  the  Gulf  coastal  plain  has  been 
investigated  by  many  of  the  most  able  geologists,  but  the  problem 
cannot  be  said  to  have  been  satisfactorily  solved.  Since  1860,  numerous 
theories  have  been  presented,  only  to  be  discarded,  at  least  in  part,  as 
more  complete  information  revealed  their  fundamental  weakness. 

Real  progress  toward  solution  dates  from  1902,  when  Hill1  advanced 
the  theory  of  secondary  deposition  of  the  domal  materials  from  saturated 
solutions  of  hot  saline  waters  ascending  from  great  depths  under  hydro- 
static head  along  structural  lines  of  weakness.  Shortly  thereafter, 
Harris,2  using  HilPs  hypothesis  as  a  basis,  explained  the  doming  and 
pronounced  uplift  associated  with  these  salt  cores  as  the  result  of  forces 
exerted  by  growing  salt  crystals.  This  was  a  marked  advance  over  the 
ideas  of  Coste3  and  Hager,4  since  no  evidence  of  igneous  intrusives,  as 
they  assumed  to  explain  the  uplifts,  had  been  found  associated  with  the 
domes.  Harris5  developed  his  theory  until  it  offered  such  apparently 
plausible  explanations  of  so  many  details  of  dome  phenomena  that  his 
hypothesis  and  conclusions  received  widespread  acceptance,  despite 
some  serious  objections,  and  today  his  theory,  somewhat  modified,  is 
considered  by  many  able  investigators  to  be  the  best  explanation  of  the 
origin  of  these  domes. 

The  immense  production  of  oil  per  acre,  the  recognition  of  the  high 
lubricating  quality  of  the  oil,  the  development  and  recognition  of  the 
efficiency  and  advantages  of  oil-burning  vessels,  with  the  subsequent 
exceptional  demand  for  fuel  oil,  and  the  resultant  advance  in  the  price 
of  coastal  crude,  have  been  responsible  for  a  prospecting  and  develop- 


1  Robert  T.  Hill:  Beaumont  Oil  Field  with  Notes  on  Other  Oil  Fields  of  the  Texas 
Region.  Jnl  Franklin  Inst.  (1902)  154, 143. 

'Gilbert  D.  Harris:  Rock  Salt  in  Louisiana.  Louisiana  Geol.  Survey  Butt.  7 
(1907)  76. 

8  E.  Coste :  Volcanic  Origin  of  Natural  Gas  and  Petroleum.  Jnl.  Canadian  Min. 
Inst.  (1903)  6,  73. 

4  Lee  Hager :  Mounds  of  the  Southern  Oil  Fields.  Eng.  &  Min.  Jnl.  (July  28, 
1904)  78, 137,  180. 

6  Gilbert  D.  Harris :  Geological  Occurrence  of  Rock  Salt  in  Louisiana  and  East 
Texas.  Econ.  Geol.  (1909)  4,  12. 


296      SECONDARY  INTRUSIVE  ORIGIN  OF  GULP  COASTAL  PLAIN  SALT  DOMES 

ment  campaign  throughout  the  coast  country,  during  the  last  5  years, 
that  has  seldom  been  equaled  when  the  present  depth  of  drilling  is 
taken  into  consideration.  This  drilling  has  produced  much  information 
relative  to  the  peculiar  characteristics  of  these  salt  domes,  with  the  result 
that  several  new  theories  of  origin  have  been  promulgated. 

One  of  the  most  ingenious  of  these  new  hypotheses  is  that  of  Norton,6 
who  thinks  that  these  salt  masses  and  their  associated  materials,  limestone 
and  gypsum,  have  been  deposited  near  the  surface  by  highly  saturated, 
thermal,  spring  waters,  such  deposition  taking  place  contemporaneously 
with  the  sedimentation  of  the  region.  He  presents  new  ideas  in  contend- 
ing that  the  limestone  cap  rock,  associated  with  many  salt  domes,  is 
due  to  deposition  of  calcareous  sinter  by  these  thermal  springs;  he  also 
suggests  that  the  gypsum  may  result  from  the  alteration  of  this  calcareous 
sinter  through  chemical  reaction  with  acid  sulfate  waters  and  hydrogen 
sulfide.  He  fails,  however,  to  offer  an  adequate  explanation  of  the 
factors  responsible  for  the  structural  deformations  connected  with  the 
salt  cores  so  that  his  theories  have  not  received  the  recognition  they 
deserve. 

Kennedy,7  in  1917,  advocated  practically  the  same  theories  but  he 
advanced  a  step  when  he  contended  that  the  domal  uplift  was  due  to 
increase  in  volume  resulting  from  the  conversion  of  limestone  into 
gypsum.  Mills  and  Wells,8  shortly  thereafter,  supported  Harris' 
theory,  removing  one  of  the  chief  objections  to  it  by  presenting  evidence 
to  show  the  effect  of  expanding  gas  on  the  deposition  of  sodium  chloride 
from  concentrated  solution.  Lucas9  later  maintained  that  the  uplift 
was  due  to  laccolithic  intrusion  at  great  depth. 

Early  in  1917,  van  der  Gracht10  called  attention  to  the  fact  that 
salt  domes  in  northwestern  Europe,  of  somewhat  similar  character  to 
those  of  the  Gulf  coastal  plain,  had  been  subjected  to  diamond  drilling, 
mining,  and  such  extensive  development  that  their  origin  had  been 
determined  beyond  much  question.  Their  formation  was  ascribed  to 
the  intrusion  en  masse  of  solid  rock  salt  into  the  overlying  strata,  the 
salt  originating  in  deeply  -buried,  primary,  bedded  deposits,  10,060 
(3040  m.),  15,000  up  to  22,000  ft.  below  the  present  surface.  His 


•Edward  G.  Norton:  Origin  of  the  Louisiana  and  East  Texas  Salines.  Trans. 
(1915)  51,  502. 

'William  Kennedy:  Coastal  Salt  Domes,  Southwestern  Assn.  Pet.  Geol.  Bull. 
1  (1917)  34. 

«R.  Van  A.  Mills  and  R.  C.  Wells:  Evaporation  at  Depth  by  Natural  Gases. 
Abstract,  Wash.  Acad.  Sci.  Jnl  (1917)  7,  309. 

•  A.  F.  Lucas :  Possible  Existence  of  Deep-seated  Oil  Deposits  on  the  Gulf  Coast. 
Trans.  (1919)  61,  501. 

10  W.  A.  I.  M.  von  Waterschoot  van  der  Gracht :  Salt  Domes  of  Northwestern 
Europe.  Southwestern  Assn.  Pet.  Geol.  Bull.  1  (1917)  85. 


W.   G.   MATTESON  297 

suggestion  of  considering  a  similar  origin  for  the  American  domes  was 
not  received  with  much  enthusiasm  until  tentatively  accepted  by  De- 
Golyer,11  in  1918,  after  rejecting  a  volcanic  origin.  E.  T.  Dumble,12 
whose  investigations  in  the  Gulf  coastal  plain  region  have  extended  over 
30  years  and  have  made  him  an  authority  on  this  area,  became  con- 
verted at  the  same  time  as  DeGolyer  but  it  remained  for  G,  Sherburne 
Rogers,18  of  the  United  States  Geological  Survey,  to  propound  and 
apply  in  detail,  through  analogy  and  otherwise,  the  European  theory  to 
the  American  domes.  Since  then,  nearly  all  opponents,  and  some 
advocates,  of  the  theories  of  Hill,  Harris,  Norton,  and  Kennedy  have 
accepted  the  primary  intrusive  origin  so  that  opinion  now  seems  to  be 
about  equally  divided  between  this  and  the  theory  of  secondary  origin 
from  ascending  saline  waters. 

Rarely  has  any  theory  gained  so  many  active  supporters  in  so  short 
a  time,  especially  where  there  had  been  previously  such  a  wide  divergence 
of  opinion.  The  primary  intrusive  theory  eliminates  some  of  the  old 
difficulties  of  long  contention  connected  with  the  previously  accepted 
American  hypotheses  and  to  some,  this  has  evidently  been  sufficient  for . 
its  acceptance.  Washburne14  apparently  has  recognized  some  of  the  diffi- 
culties involved  in  this  theory  but  his  supporting  argument  fails  to 
strengthen  the  case. 

The  purpose  of  this  paper  is  to  show  that  the  European  intrusive 
origin  of  salt  domes,  as  applied  to  American  occurrences  by  Rogers,  does 
not  comply  with  facts  and  does  not  satisfy  fundamental  conditions  as 
observed  in  the  field  and  is,  therefore,  not  directly  applicable;  also,  to 
propose  a  theory  that  apparently  complies  with  all  field  observations  and 
eliminates  many  of  the  objections  to  the  present  theories. 

INTRUSIVE  ORIGIN  AS  PROPOSED  BY  ROGERS 

Rogers16  contends  that  the  salt  plugs  of  the  Gulf  coastal  plain  are 
off  shoots  of  deeply  buried  bedded  deposits  of  salt  that  have  been  subjected 
to  great  pressure  or  thrust,  and  have  been  partly  squeezed  upwards  in  a 
semiplastic  condition  along  lines  of  weakness.  He  admits  that  he  has 
no  adequate  explanation  for  the  formation  and  intimate  association  of  the 
cap-rock  materials  and  the  salt  but  suggests  that  the  cap  rock  might  have 
been  formed  subsequent  to  the  salt  or  that  an  overlying  anhydrite  bed  or 


11  E.  L.  DeGolyer:  Theory  of  Volcanic  Origin  of  Salt  Domes.  Trans.  (1919)  61, 
456. 

18E.  T.  Dumble:  Discussion  on  paper  noted  in  Footnote  11. 

18  G.  Sherburne  Rogers:  Intrusive  Origin  of  the  Gulf  Coast  Salt  Domes.  Econ. 
Geol  (1918)  13,  447. 

14  Chester  W.  Washburne:  Oil-field  Brines.    See  page  269. 

"Rogers:  Op.  tit. 


298      SECONDARY  INTRUSIVE  ORIGIN  OF  GULF  COASTAL  PLAIN  SALT  DOMES 

block  was  brought  up  with  the  salt  during  intrusion.  Since  the  presence 
of  nearly  a  hundred  salt  domes  has  been  recorded  in  the  Gulf  coastal 
plain  province  and  practically  all  show  varying  thicknesses  of  cap  rock, 
the  theory  which  postulates  that  nature  should  perform  with  such  har- 
mony and  cooperation  as  to  provide  an  overlying  bed  of  anhydrite  at 
just  the  specific  point  of  intrusion  for  every  salt-dome  occurrence  is 
constructed  on  rather  a  precarious  foundation  of  probability. 

Rogers  prefaces  his  discussion  by  admitting  that  any  acceptable 
theory  must  consider  and  explain  plausibly: 

1.  The  source  of  the  salt  and  the  manner  in  which  it  attained  its 
present  position. 

2.  The  sharp  local  upthrust  of  the  sediments  surrounding  the  salt  core. 

3.  The  source  and  relations  of  the  gypsum,  anhydrite,  limestone, 
dolomite,  and  sulfur  usually  found  above  the  salt. 

4.  The  alignment  of  the  domes  and  their  relationship  to  the  main 
structural  features  of  the  region. 

5.  The  origin  and  mode  of  accumulation  of  the  oil  associated  with 
most  of  the  domes. 

In  attempting  to  prove  his  theories,  four  points  are  cited  by  Rogers16 
as  favoring  his  hypotheses ;  namely : 

1.  The  sharp  local  doming  of  the  sediments  above  the  salt — doming 
of  a  type  that  several  writers  have  stated  is  known  to  have  been  produced 
elsewhere  only  by  (igneous)  intrusion. 

2.  The  flow  structure,  crystal  orientation,  and  cleavage  of  the  salt 
itself,  indicative  of  pronounced  movement  in  a  vertical  direction. 

3.  The  plasticity  of  salt,  which  is  considerable  at  ordinary  tempera- 
tures and  increases  rapidly  with  heat. 

4.  The  clear  evidence  that  similar  domes  in  other  countries  have 
actually  been  formed  under  the  conditions  postulated. 

In  addition,  Rogers  admits  that  the  proof  of  his  conclusions  and  the 
acceptance  of  the  primary  intrusive  theory  depends  on  the  ability  to 
show:  A  reasonable  possibility  that  bedded  salt  deposits  exist  at  depth 
beneath  the  Gulf  Coast  and  the  possibility  that  forces  competent  to  pro- 
duce the  results  observed  have  been  operative. 

Possibility  of  Bedded  Salt  Deposits  at  Depth  Within  Gulf  Coastal  Plain 

Province 

The  reasonable  possibility  of  the  existence  of  bedded  deposits  of  rock 
salt  at  depth  underlying  the  present  Gulf  coastal  plain  province  is  the 
foundation  on  which  the  present  accepted  intrusive  origin  of  these  salt 
domes  has  been  erected.  Eliminate  this  possibility  and  the  superstruc- 
ture of  the  theory  crumbles. 

"  Op.  tit.,  468. 


W.  G.  MATTESON  299 

Rogers17  assumes  the  existence  of  Permian  salt  deposits  in  Permian 
strata  underlying  the  Gulf  coastal  plain  province.  He  concedes  that 
positive  evidence  to  indicate  even  the  existence  of  Permian  rocks  has  not 
been  forthcoming  although  over  a  thousand  deep  tests  have  been  drilled, 
some  of  which,  in  the  Cretaceous  belt  bordering  the  coastal  plain,  pene- 
trated the  full  measure  of  Cretaceous  rocks  but  failed  to  find  underlying 
beds  of  Permian  age.  The  Texas  Panhandle  region,  an  entirely  different 
province  with  different  conditions  of  sedimentation  and  200  mi.  (321  km.) 
removed,  is  made  up  of  Permian  strata,  which  contain  beds  of  gypsum 
and  salt.  Rogers18  cites  N.  H.  Darton,  who  has  studied  the  deposits  of 
the  Panhandle,  to  the  effect  that  he  regards  the  existence  of  another  and 
similar  salt-bearing  basin  to  the  southeast  as  conjectural  but  entirely 
possible.  In  addition  thereto,  Rogers  adds: 

There  is  but  little  positive  evidence  either  for  or  against  the  supposition  that  deep- 
seated  bedded  salt  deposits  exist  in  the  coastal  region.  Wells  penetrating  4000  ft.  of 
Tertiary  sediments  have  found  no  salt  and  it  is  evident  that  if  any  exists  it  is  in  the 
Mesozoic  or  Paleozoic  rocks.  No  bedded  salt  deposits  of  any  consequence  are  known 
to  occur  in  the  Cretaceous  or  Triassic  beds  and  there  seems  little  real  basis  for  assuming 
their  presence.  In  view  of  the  lack  of  positive  evidence,  it  is  perhaps  permissible  to 
beg  the  question  and  argue  that  the  best  evidence  of  buried  salt  beds  is  the  domes 
themselves. 

This  seems  to  be  arguing  in  a  circle  and  is  proof  of  the  insecure  and 
uncertain  foundation  on  which  the  theory  is  built.  E.  T.  Dumble,19 
in  a  paper  written  three  years  previous  to  that  of  Rogers,  discusses  and 
makes  comparative  notes  on  the  occurrence  of  petroleum  in  eastern 
Mexico  and  the  Gulf  coastal  plain,  as  follows : 

To  the  southward  in  Central  Mexico,  very  complete  sections  are  found  of  both 
Trias  and  Jura,  but  if  the  waters  of  those  periods  ever  reached  the  Texas  coast,  no 
evidence  remains  to  prove  it. 

Referring  to  the  oil-bearing  Woodbine  sands  in  northern  Louisiana, 
he  says: 

Between  this  great  Louisiana  field  on  the  north  and  the  greater  Mexican  field  on 
the  south,  there  is  an  interval  of  more  than  600  mi.  in  which  these  formations  are  not 
found  within  the  Coastal  area,  unless  some  portion  of  the  basal  Eagle  Ford  shale  may 
represent  a  time  equivalent,  and  even  if  that  be  the  case,  no  oil  deposits  are  found. 
We  have  no  evidence  whatever  of  any  Permian  deposits  southeast  of  the  Lampasas 
geanticline  nor  of  the  continuation  of  the  Woodbine  as  an  oil  horizon  as  far  southward 
as  the  coast. 

Dumble 's  statements  have  an  important  bearing  because  if  conditions 
in  the  Texas-Louisiana  region  prevented  the  deposition  of  the  Triassic  and 
Jurassic  observed  farther  south,  the  most  reasonable  deduction  points  to 

17  Op.  cit.,  476-477.  "  Op.  tit.,  476-477. 

19  E.  T.  Dumble:  Occurrences  of  Petroleum  in  Eastern  Mexico  as  Contrasted 
with  those  in  Texas  and  Louisiana.  Trans.  (1915)  52,  250. 


300      SECONDABY  INTRUSIVE  ORIGIN  OP  GULP  COASTAL  PLAIN  SALT  DOMES 

such  conditions  maintaining  during  Permian  times,  thereby  eliminating 
the  possibility  of  the  presence  of  Permian  strata.  This  conclusion  seems 
inevitable  when  the  negative  character  of  hundreds  of  well  records  are 
considered. 

In  a  much  later  paper,  Dumble20  agrees  with  Rogers  as  to  the  intru- 
sive origin  of  the  salt  domes  from  bedded  deposits  of  rock  salt  at  depth, 
but  realizing  the  extremely  weak  nature  of  the  foundation  on  which 
Rogers  builds  his  theory  by  assuming  the  presence  of  Permian  beds, 
Dumble  cites  what  he  believes  is  more  logical  evidence  as  to  the  possi- 
bility of  buried  salt  strata.  From  general  stratigraphic  considerations, 
he  believes  there  were  three  periods  in  Mesozoic  and  Tertiary  times  that 
were  favorable  for  the  development  of  salt  deposits: 

The  association  of  the  gypsum,  salt,  and  anhydrite  suggest  their  derivation  from 
sea  water  by  evaporation.  The  Trinity  in  Arkansas  carries  considerable  beds  of 
gypsum,  a  condition  which  was  duplicated  in  west  Texas,  where,  in  the  Malone  Moun- 
tains, we  have  hundreds  of  feet  of  gypsum  of  Lower  Cretaceous  age.  There  is,  there- 
fore, no  reason  why  salt  and  gypsum  deposits  of  this  age  may  not  be  expected  in  the 
area  of  northeast  Texas  occupied  by  the  interior  domes. 

A  second  period  favorable  for  such  deposits  is  found  in  the  interval  between  the 
Comanchean  and  the  Upper  Cretaceous.  While  we  have  no  such  positive  evidence 
of  the  accumulation  of  such  deposits  of  sea  salts  at  this  period,  the  fact  that  for  hun- 
dreds of  miles  the  contact  between  the  Buda  Limestone,  which  marked  the  close  of 
Comanchean  deposition,  and  the  Eagle  Ford  shows  no  sign  of  erosion  proves  that 
during  the  long  period  that  elapsed  between  them,  the  top  of  the  Comanchean  must 
have  remained  at  or  near  sea  level  and  in  such  relation  to  it  that  no  terrigenous  sedi- 
ments could  be  laid  down  on  it.  In  the  more  littoral  zone  of  northeast  Texas,  the 
Buda  is  represented  by  clays  and  the  conditions  would  be  even  more  favorable  for  the 
formation  of  salt  basins  and  the  accumulation  of  gypsum  and  salt  prior  to  the  begin- 
ning of  Upper  Cretaceous  sedimentation.  There  is  every  reason  to  believe,  therefore, 
that  the  gypsum  and  salt  found  in  connection  with  the  interior  domes  may  have  been 
deposited  during  the  Lower  Cretaceous  or  in  the  Mid-Cretaceous  interval. 

That  the  withdrawal  of  the  sea  at  the  close  of  the  Eocene  was  accompanied  by  the 
deposition  of  beds  of  massive  gypsum  is  clearly  shown  at  the  southern  end  of  the  belt 
of  the  Gulf  Coast  Eccene  on  the  Conchas  River  in  Mexico.  Here  the  Frio  clays,  which 
are  the  uppermost  Eocene  beds  and  probably  of  Jackson  age,  form  a  large  portion  of 
the  Pomerane  Mountains.  They  carry  in  their  upper  portion  heavy  beds  of  gypsum, 
alabaster,  and  selenite,  interbedded  with  clays .  While  similar  conditions  are  not  known 
to  have  positively  occurred  in  eastern  Texas,  it  is  probable  that  they  did,  and  that 
salt  and  gypsum,  which  occur  in  connection  with  the  coastal  domes,  was  deposited 
at  the  time  of  this  emergence  and  prior'to  the  deposition  of  the  Corrigan  sands. 

Since  the  publication  of  the  papers  by  Rogers  and  Dumble,  the 
development  in  these  areas  has  furnished  sufficient  reasons  for  believing 
that  salt  deposits  do  not  exist  and  were  not  formed  in  the  epochs  outlined 
by  Dumble: 

1.  Numerous  wells,  scattered  over  the  coastal  plain  province  and  drilled 

10  E.  T.  Dumble :  Discussion  on  Theory  of  Volcanic  Origin  of  Salt  Domes.  Trans. 
(1919)  61,  470. 


W.   G.   MATTESON  301 

as  deep  as  5000  ft.  (1520  m.),  have  failed  to  record  the  presence  of  salt 
beds  although  the  formations  in  which  Dumble  predicts  their  presence 
have  been  penetrated. 

2.  Deep  wells,  miles  from  the  Trinity  contact,  have  encountered 
neither  gypsum  in  quantity  nor  rock  salt  in  eastern  Texas. 

3.  Deep  wells,  penetrating  the  Lower  Cretaceous  on  the  Sabine  uplift, 
have  given  no  indications  of  gypsum  and  rock  salt. 

4.  The  Cretaceous  deposits  of  the  Malone  Mountains  are  in  a  belt 
where  Permian  rocks,  carrying  salt  and  gypsum,  occur  in  vast  quantity; 
no  such  association  is  known  in  eastern  Texas.     Moreover,  the  Malone 
Mountains  are  in  a  different  physiographic  and  stratigraphic  province 
and  such  deductions  as  are  suggested  by  Dumble  are  dangerous  and  not 
justified.     Intimate  studies  of  the  sedimentation  processes  affecting  the 
Gulf  coast  province  show  such  processes  to  be  complex  and  varying  in 
character  to  such  an  extent  that  even  the  same  formation,  within  short 
distances,  may  be  hardly  recognizable  from  its  lithologic  character.     A 
good  illustration  is  the  Fleming  clays,  which  are  palustrine  at  their  out- 
crop and  non-bituminous  and  marine  a  few  miles  south  of  their  outcrop 
and  bituminous.     Therefore,  even  if  certain  conditions  existed  in  Ar- 
kansas or  western  Texas,  this  fact  is  no  safe  basis  for  assuming  similar 
conditions  to  exist  in  adjacent  territory  owing  to  the  factors  influencing 
sedimentation. 

5.  Recent  deep  tests  have  proved  that  the  conditions  obtaining  at  the 
end  of  the  Eocene  in  Mexico  probably  did  not  continue  northward  into 
Texas.     A  well  recently  drilled  by  the  Kleberg  County  Oil  &  Gas  Co.,  7 
mi.   (11  km.)  south  of  Kingsville,  Tex.,  to  a  depth  of  nearly  4000  ft. 
(1200  m.)  penetrated  the  Yegua  clays  probably  at  around  1850  ft.  and 
probably  stopped  in  the  Marine  beds  or  the  Wilcox;  it  showed  insigni- 
ficant quantities  of  gypsum  and  no  beds  of  rock  salt.     Two  tests  of  3300 
and  3500  ft.,  drilled  by  the  Gulf  Production  Co.  at  White  Point,  near 
Corpus  Christi,  were  abandoned  close  to  the  bottom  of  the  Yegua,  half 
way  through  the  total  thickness  of  the  Eocene  formations;  they  showed 
insignificant  amounts  of  gypsum  and  no  rock  salt.     The  evidence  is  clear 
that  the  gypsum  is  thinning  rapidly  to  the  north  from  the  Mexican 
border  and  the  salt  beds  presumed  by  Dumble  do  not  exist.     The  author 
recently  collected  fossils  from  the  well  of  the  Texas  Oil,  Gas  &  Mineral 
Products  Co.,  in  Grimes  County,  which  Kennedy  and  Dumble  identified 
as  probably  of  Cook  Mountain  age.     The  author  examined  the  samples  of 
cuttings  taken  from  this  well  but  found  absolutely  no  evidence  of  rock 
salt.    Another  well  in  the  same  county  and  several  hundred  feet  deeper 
records  the  same  results.     If  the  quantity  of  salt  necessary  for  the 
formation  of  so  many  salt  domes  existed  in  the  form  of  bedded  deposits, 
some  of  the  numerous,  deep,  wildcat  tests  drilled  during  the  past  5  years 
throughoutjthe  Gulf  coast  province  would  record  the  fact.     It  should  also 


302      SECONDARY  INTRUSIVE  ORIGIN  OF  GULF  COASTAL  PLAIN  SALT  DOMES 

be  borne  in  mind  that  gypsum  and  salt  are  not  always  associated  together, 
even  if  the  combined  occurrence  is  common.  The  presence  of  gypsum, 
therefore,  does  not  necessarily  signify  the  presence  of  salt. 

In  presenting  this  controvertive  evidence,  over  a  thousand  well  logs 
have  been  examined  by  the  writer.  Beginning  with  the  5000-ft.  deep  test, 
starting  at  the  Fort  Worth  limestone  horizon  of  the  Lower  Cretaceous 
formation  at  Polytechnic  near  Fort  Worth,  Tex.,  and  including  an  area 
as  far  as  New  Iberia,  La.,  to  the  southeast,  and  Brownsville,  Tex.,  to  the 
southwest,  not  one  deep  test,  except  those  on  defined  salt  domes,  has 
encountered  deposits  of  salt  so  as  to  warrant  the  reasonable  conclusion 
that  extensive  bedded  deposits  of  such  substance  existed  at  depth. 
Hence  the  foundation  of  the  intrusive  theory  of  salt  domes,  as  promul- 
gated by  Rogers,  must  be  rejected. 

Intensity  of  Forces  Producing  Intrusiort 

Rogers,21  in  developing  the  theory  of  intrusive  origin,  states  that  it  is 
necessary  to  show  that  forces  competent  to  produce  the  results  observed 
have  been  operative,  and  suggests  three  possible  causes  that  might  pro- 
duce the  pressure  and  force  demanded,  namely,  igneous  intrusion  at 
great  depth,  the  weight  of  the  overlying  sediments,  and  lateral  or  com- 
pressive  thrust.  He  dismisses  the  first  two  causes  as  either  improbable 
or  not  sufficiently  competent  to  produce  the  results  observed  but  concen- 
trates on  the  third  cause  as  the  most  plausible,  basing  his  belief  on 
analogy  with  European  conditions.  Van  der  Gracht22  describes  the 
salt-dome  area  of  northwestern  Europe  as  a  geosynclinal  basin,  in- 
tensely folded  and  faulted.  So  intense  has  been  the  folding  that  some 
of  the  folds  have  been  overthrust.  In  discussing  the  Roumanian  salt 
domes,  van  der  Gracht  states  "that  orogenetic  pressure  was  the  cause  of 
these  upthrusts  is  evident  from  the  whole  structure  of  the  region.  We 
find,  however,  that  fairly  often  the  continuing  lateral  compression  has 
squeezed  out  the  stem  of  the  salt  core,  perhaps  even  to  the  extent  of 
separating  the  saline  mass  at  the  surface  from  its  roots  in  the  Miocene." 

Evidently  the  lateral  compression  forces  brought  into  play  in  the 
European  areas  have  been  enormous  and  much  more  intense  and  complex 
than  anything  observed  in  the  Texas-Louisiana  area,  which  is  also  mono- 
clinal  in  structure  as  compared  to  the  geosynclinal  condition  in  Europe. 
Drilling  adjacent  to  the  American  domes  shows  conclusively  that  these 
domes  are  not  situated  along  the  axes  of  highly  compressed  and  arched 
folds,  as  van  der  Gracht  describes  for  Germany,  Holland,  and  Roumania. 
The  disturbances  in  the  Gulf  coastal  plain  province  apparently  partake 
largely  of  the  nature  of  block  faulting.  Lateral  compression  on  a  small 
scale  has  undoubtedly  been  a  complement.  While  these  disturbances 

81  Op.  cit.,  481.  "van  der  Gracht:  Op.  cit. 


W.    G.    MATTESON  303 

are  probably  sufficient  to  cause  intrusion  of  salt  masses  to  some  extent, 
the  evidence  is  strongly  against  such  stresses  being  sufficient  to  cause 
movement  of  a  salt  plug  from  a  depth  of  10,000  to  20,000  ft.  through 
thousands  of  feet  of  overlying  strata,  as  claimed  by  Rogers.  On  this 
point,  Norton23  says,  "If  salt  in  regular  bedding  exists  in  Louisiana  and 
Texas,  it  has  never  been  penetrated  by  the  drill.  If  we  assume  that  it 
exists  at  depths  greater  than  have  been  reached,  and  has  been  elevated 
to  the  surface  by  an  anticlinal  development,  the  assumption  is  not  sup- 
ported by  evidence  that  such  mountain-building  forces  have  been  at 
work." 

Analogies  between  European  and  American  Domes 

So  much  has  been  said  about  the  European  domes  and  such  constant 
reference  has  been  made  to  the  origin,  character,  and  the  similarity  of 
these  domes,  in  many  ways,  to  the  American  occurrences,  that  it  might 
be  well  to  present  briefly  the  evidence  on  which  the  origin  of  the  European 
domes  has  been  formulated. 

1.  The  undoubted  presence  of  a  great  thickness  of  upper  Permian 
red  marls  and  dolomites,  lying  at  a  depth  of  a  few  thousand  up  to  22,000 
ft.,  and  containing  a  nearly  continuous  deposit  of  rock  salt  averaging 
about  1000  ft.  in  thickness  in  the  southern  area  of  its  deposition  but  in- 
creasing to  more  than  2000  ft.  farther  north,  and  possibly  considerably 
more  in  deeper  basins,  where  the  original  mother  bed  has  not  been  reached. 

2.  The  presence  in  and  throughout  the  salt  cores  of  the  domes  of 
Europe  of  anhydrite  and  intercalations  of  valuable  potassium  salts  such 
as  is  found  in  the  original  beds. 

3.  Areas  and  blocks  of  Permian,  Triassic,  Jurassic,  and  Cretaceous 
rocks  exposed  at  or  lying  close  to  the  surface,  having  been  pushed  up 
through  thousands  of  feet  of  overlying  Tertiary  and  Quaternary  deposits. 

4.  The  domes  occur  in  and  along  folds  or  faults  in  geosynclinal  basins 
where  compression  and  folding  have  been  very  intense. 

5.  Lines  of  weakness  have  been  developed  in  two  main  directions, 
northwest  to  southeast  and  northeast  to  southwest;  wherever  these  in- 
tersect high  uplifts  occur. 

To  quote  van  der  Gracht  :24 

As  a  rule,  red  Permian  marls  and  often  blocks  of  massive  Triassic  sandstones  or 
limestones  have  been  pushed  upwards  with  the  salt,  and  now  appear  near,  or  some- 
times even  at  the  surface,  sometimes  standing  out  in  relief  as  curious  red  rocky  hills 
amidst  the  Quaternary  plain.  The  most  striking  of  these  is  the  red,  rocky  island  of 
Helgoland  in  the  North  Sea,  off  the  mouth  of  the  Elbe  River.  .  .  .  The  main 
point  is,  however,  that  invariably  the  rocks  associated  with  the  saline  core  prove  that 
the  plug  has  its  roots  in  the  Permian  rock  salt,  however  great  the  depth  of  this  latter 
may  be,  even  up  to  20,000  feet. 

23  Norton:  Op.  tit.,  503.  "  Op.  tit.,  88. 


304      SECONDARY  INTRUSIVE  ORIGIN  OF  GULF  COASTAL  PLAIN  SALT  DOMES 

In  comparing  the  evidence  presented  by  the  Texas-Louisiana  domes,  it 
is  to  be  noted  that:  p 

1.  There  is  no  direct,  positive,  or  probable  evidence  of  the  presence 
of  deeply  buried  bedded  deposits  of  rock  salt  nor  has  deep  and  extensive 
drilling  revealed  a  reasonable  possibility  of  the  existence  of  the  same. 

2.  Potassium  salts,  such  as  are  commonly  associated  with  bedded 
deposits  of  rock  salt,  are  practically  missing  and  only  small  quantities 
of  anhydrite,  not  at  all  comparable  with  what  should  accompany  bedded 
deposits,  are  observed.     This  anhydrite  is  practically  always  found  as 
part  of  the  cap  rock  and  not  embedded  in  the  salt. 

3.  Areas  and  blocks  of  older,  underlying  formations  have  not  been 
upthrust  so  as  to  be  exposed  at  or  to  lie  near  the  surface.     The  only 
foreign  material  observed  in  connection  with  the  American  domes  was 
a  small  mass  of  red  sandstone  at  Avery's  Island,  the  presence  of  which 
can  be  explained  in  various  ways. 

4.  The  American  domes  are  on  a  gently  dipping  monocline  and,  in 
general,  orogenic  disturbance  has  not  been  intense. 

5.  Lines  of  weakness  have  been  developed  in  the  American  domes  in 
two  main  directions,  northwest  to  southeast  and  northeast  to  south- 
west; wherever  these  intersect,  doming  is  apt  to  occur. 

Thus  of  the  five  fundamentals  affecting  and  determining  the  origin 
of  the  European  domes,  only  one  is  in  any  way  similar  and  is  duplicated 
in  the  Texas-Louisiana  area.  It  is  true  that  the  American  domes  have 
cores  of  salt  as  in  Europe,  that  the  salt  is  overlain  by  gypsum  and  lime- 
stone as  in  Europe,  and  that  the  deformation  partakes  of  a  quaquaversal 
nature;  in  other  words,  the  form  and  the  material  of  the  domes  bear  close 
and  striking  similarity  in  general  features,  like  two  veins  of  copper,  but 
as  the  veins  of  copper  may  have  widely  divergent  origin,  so  does  the  origin 
of  the  European  domes,  according  to  evidence  presented,  vary  consider- 
ably from  what  facts  observed  in  the  field  must  establish  for  the  American 
occurrences. 

Conclusions 

The  intrusive  origin  of  the  Gulf  coast  salt  domes,  as  promulgated  by 
Rogers,  is  not  tenable,  in  that  sufficient,  well-established,  definite  data 
cannot  be  adduced  to  substantiate  the  fundamental  requirements  con- 
stituting the  basis  of  the  theory,  and  the  theory  does  not  conform  to  nor 
satisfy  the  numerous  facts  and  details  observed  in  association  with  the 
coastal  domes. 

SPECIAL  CHARACTERISTICS  ASSOCIATED  WITH  SALT  DOMES  OF 
THE  GULF  COASTAL  PLAIN  PROVINCE 

Any  acceptable  theory  relative  to  the  origin  of  the  Texas-Louisiana 
domes  must  conform  to  and  explain,  even  to  a  reasonable  degree  of  detail 


W.   G.   MATTESON  305 

the  unusual  structural,  stratigraphic,  and  mineralogical  peculiarities  of 
these  domes.  A  tabulated,  descriptive  review  of  their  characteristics 
shows  the  following  features : 

1.  A  core  of  domal  materials  which  includes  rock  salt,  gypsum,  anhy- 
drite, limestone,  dolomite,  and  sulfur. 

2.  Pure  rock  salt  forms  the  greater  portion  of  the  core.     This  salt 
is  generally  overlain  and  in  direct  contact  with  a  thick,  massive  core  or 
bed  of  gypsum.    Small  quantities  of  anhydrite  are  found  occasionally 
in  this  gypsum.     Sometimes  the  gypsum  is  capped  by  a  thin  to  thick 
deposit  of  limestone,  and  limestone  is  generally  found  intermixed,  in- 
cluded within,  and  scattered  throughout  the  gypsum.     The  sulfur  occurs 
as  crystals  or  crystalline  masses  in  cavities  in  the  limestone  and  gypsum. 
The  dolomite  is  due  to  the  alteration  of  limestone  masses. 

3.  The  salt  is  relatively  pure;  it  carries  no  potassium  compounds, 
which  are  characteristic  of  bedded  deposits  from  sea  water;  neither  are 
broken  boulders  or  strata  of  anhydrite  and  limestone  found  within  the 
main  salt  mass. 

4.  A  microscopic  examination  of  crystals  of  the  upper  portion  of  the 
salt  sometimes  shows  included  gypsum  crystals. 

5.  These  cores  of  domal  materials  are  roughly  cylindrical  or  elliptical 
in  outline,  their  vertical  dimensions  often  exceeding  their  diameters  or 
longer  horizontal  axes. 

6.  The  cap-rock  material  of  gypsum  and  limestone  does  not  overlap 
the  salt  mass  to  any  extent. 

7.  The  domal  core  is  gently  rounded  to  flat  on  top  with  dipping  sides 
of  60  to  90  degrees. 

8.  Stringers,  sheets,  or  pencils  of  salt  and  gypsum  are  sometimes  found 
projecting  from  the  main  core;  sometimes  these  minor  deposits  appear  to 
be  completely  disconnected  or  severed  from  the  main  core. 

9.  Domal  materials  appear  to  be  localized  and  are  not  found  in 
isolated  quantity  at  any  distance  from  the  domal  core  with  the  possible 
exception  of  limestone.    Limestone  so  found  is  part  of  a  stratigraphic 
unit  and  is  not  of  the  same  lithologic  character  as  the  domal  material. 

10.  Crystals  of  salt  sometimes  show  elongation  in  a  vertical  direction, 
the  salt  often  shows  pronounced  cleavage  and  plication,  and  the  gypsum 
is  cavernous  and  often  fractured,  shattered,  and  broken. 

11.  Strata  immediately  adjacent  to  the  domal  core  are  abruptly 
domed  or  upturned  and  highly  inclined,  and  show  considerable  deforma- 
tion.    The  strata  dip  from  20°  to  50°  but  appear  practically  undisturbed 
and  flat  lying  within  relatively  short  distances  from  the  core. 

12.  The  domes  apparently  have  a  definite  alignment  in  northeast  to 
southwest  and  northwest  to  southeast  directions. 

13.  Often  the  top  of  the  domal  material  lies  at  or  close  to  the  surface; 
at  other  times  at  considerable  depth.     In  some  instances,  the  salt  has 

YOL.  1XV. — 20. 


306      SECONDARY  INTRUSIVE  ORIGIN  OF  GULP  COASTAL  PLAIN  SALT  DOMES 

never  been  penetrated  and  in  a  few  cases,  not  even  the  main  gypsum  mass 
has  been  encountered. 

14.  The  presence  of  certain  recognized  horizons  at  or  near  the  surface, 
which  normally  should  be  found  at  considerable  depth,  indicates  uplift 
in  the  vicinity  of  the  core  of  1000  to  3000  feet. 

15.  Several  of  the  domes  show  faulting,  and  radial  faulting  from 
the  core  is  believed  to  be  more  general  than  has  been  indicated. 

16.  Some  domes  are  featured  on  the  surface  by  slight  to  abrupt 
more  or  less  circular  mounds  or  elongated  ridges;  others,  by  central 
depressions  surrounded  by  hills;  while  others  are  absolutely  lacking  in 
topographic  characteristics. 

17.  In  domes  reproductive  of  oil,  the  oil  is  found  on  the  east,  south- 
east, south,  or  southwest  side  in  most  instances. 

19.  No  foreign  material  in  quantity,  such  as  blocks  and  boulders  of 
deeply  buried  strata,  is  found  in  the  salt. 


EVIDENCE  OF  SECONDARY  DEPOSITION 

After  studying  these  domes  in  the  field,  reviewing  the  features  asso- 
ciated with  them,  and  noting  especially  from  examination  of  numerous 
logs  and  some  surface  excavations,  the  intimate  contact  relationship  of 
the  domal  materials,  there  remains  practically  no  doubt  that  the  domal 
materials  are  secondary  in  character;  that  they  have  been  formed  under 
similar  conditions  of  time  and  deposition,  and  that  any  acceptable  theory 
of  origin  must  explain  this  type  and  intimacy  of  relationship  and  the  proc- 
esses whereby  it  has  been  developed.  In  other  words,  no  theory  is  ac- 
ceptable that  explains  the  origin  and  position  of  the  salt  and  not  that  of 
the  cap  rock. 

Attention  has  been  called  to  the  fact  that  practically  no  potassium 
or  allied  salts,  common  to  original  bedded  deposits  or  deposits  resulting 
from  the  evaporation  of  sea  water,  are  present  and  alternations  of  beds 
of  salt,  gypsum,  anhydrite,  and  limestone  are  unknown.  Neither  is  the 
salt  core  to  any  extent  contaminated  or  intercalated  with  silts,  muds, 
or  any  foreign  deposits  or  substances  but  is  so  relatively  pure  that 
deposition  from  solution  appears  to  be  conclusive.  The  author  knows 
of  no  single  instance  where  the  cap-rock  material  is  completely  and  wholly 
separated  from  the  main  salt  core  by  intervening  sedimentation  or  strata. 
There  are  instances,  as  at  Barber's  Hill,  where  the  drill  has  encountered 
boulders  of  gypsum  in  sand  when  drilling  through  the  cap  rock  and  also 
salt,  intermixed  with  sand,  but  more  extensive  drilling  has  shown  the 
cap-rock  material  to  lie  in  direct  contact  with  the  salt,  pointing  to  deposi- 
tion and  formation  in  one  period. 


W.  G.  MATTBSON  307 

THEORY  OF  SECONDARY  INTRUSIVE  ORIGIN 

Although  the  sponsors  of  the  intrusive  origin  of  the  Gulf  coast  salt 
domes  did  not  specifically  qualify  the  same,  the  author  has  taken  that 
liberty  here  in  order  to  make  the  distinction  between  this  and  the  theory 
about  to  be  proposed  absolutely  clear.  The  designation  of  the  older 
theory  as  primary  intrusive  is  in  conformance  with  the  statement  of 
those  proposing  the  theory  that  the  salt  so  intruded  was  an  offshoot 
of  an  original  bedded  or  primary  salt  deposit  existing  at  great  depth. 
After  presenting  a  concise  statement  of  the -secondary  intrusive  origin 
of  the  Gulf  coast  salt  domes,  it  is  proposed  to  discuss  the  facts  and 
arguments  supporting  and  proving  the  same. 

The  secondary  intrusive  origin  of  salt  domes  states  that  hot,  saline, 
saturated  to  supersaturated  solutions  or  brines,  accompanied  by  vast 
quantities  of  gas,  ascending  along  lines  of  structural  weakness,  deposited, 
by  the  action  of  various  and  several  agencies  hereinafter  discussed,  the 
domal  materials  relatively  near  the  surface;  that  the  initial  period  of 
movement  and  uplift,  caused  by  the  force  of  growing  crystals  and  the 
increase  in  volume  in  the  conversion  of  limestone  to  gypsum,  occurred 
contemporaneously  with  the  formation  of  the  domal  materials  and 
sedimentation,  causing  gradual  uplift  locally  as  the  surrounding  area 
was  sinking;  that  erosion  over  a  considerable  time  interval  ensued, 
removing  part  or  all  of  the  sediments  capping  the  domal  materials  and, 
in  some  instances,  portions  of  the  domal  material  itself,  to  be  followed 
by  another  period  of  sedimentation,  deposition,  and  uplift,  with  several 
minor  phases,  during  which  time  sufficient  lateral  thrust  and  compression 
was  operative  to  cause  gradual  upward  movement  or  intrusion  of  the 
domal  materials  en  masse  into  the  overlying  strata,  producing  thereby, 
together  with  the  first  period  of  uplift,  the  deformation,  doming,  and 
general  conditions  as  observed  at  the  present  day. 

Origin  and  Formation  of  Domal  Materials 

Kennedy,25  Washburne,*6  DeGolyer,27  Deussen,28  Norton,29  and 
others  have  conceded  the  secondary  nature  and  origin  of  the  gypsum 
and  limestone  cap  rock  overlying  the  salt  of  the  coastal  domes.  The 
intimate  contact  relationship,  and  other  evidence,  gained  from  several 
years  of  personal  examination  of  these  domes  and  from  the  study  of 
hundreds  of  well  logs,  indicates  that  all  the  domal  materials ,  including 

86  Op.  cit.,  56. 

86  Op.  cit.,  4-8. 

87  E.  L.  DeGolyer:  Origin  of  the  Cap  Rock  of  the  Gulf  Coast  Salt  Domes.    Econ. 
Geol  (1918)  13,  616. 

88  Alexander  Deussen :  The  Humble  Oil  Field.     Southwestern  Assn.  Pet.  Geol. 
Butt.  1  (1917)  74. 

89  Op.  cit,  508. 


308      SECONDARY  INTRUSIVE  ORIGIN  OF  GULF  COASTAL  PLAIN  SALT  DOMES 

the  salt,  were  deposited  under  similar  conditions,  by  similar  agencies, 
and  closely  following  one  another.  It  appears  most  likely  that  the 
original  domal  materials  consisted  only  of  limestone,  probably  in  the 
form  of  travertin,  and  salt,  the  gypsum  being  the  result  of  the  conversion 
of  the  limestone  through  the  action  of  sulfuric  acid  and  hydrogen  sulfide- 
bearing  waters  and  gases.  There  may  be  some  question  as  to  which 
was  deposited  first,  the  limestone  or  the  salt.  Norton30  gives  strong 
evidence  to  support  his  contention  that  the  limestone  was  precipitated 
and  then  the  salt,  but  Kennedy  takes  the  opposite  view.  Norton  states 
the  reasons  for  his  conclusions  as  follows: 

Hot  ascending  solutions,  containing  calcium  and  magnesium  carbonates,  sodium 
chloride,  carbon  dioxide,  with  varying  amounts  of  hydrogen  sulfide,  mingled  with  the 
artesian  saline  waters  of  the  Cretaceous  beds.  These  waters  were  forced  to  the  sur- 
face by  the  hydrostatic  head  of  the  region,  through  channels  that  were  opened  by 
faulting,  etc. 

Great  deposits  of  travertin  or  calcareous  sinter,  similar  to  the  deposit  at  Winn- 
field,  La.,  were  formed  around  the  thermal  springs  that  issued  from  these  openings, 
the  sinter  continuing  to  build  as  long  as  the  hydrostatic  head  was  sufficient  to  main- 
tain the  flow  ....  Contemporaneously  with  the  building  of  these  suiters,  sands 
and  clays  were  deposited  around  their  bases.  At  times,  owing  to  the  suddenly 
increased  activity  of  these  springs  resulting  from  downward  movement  and  relative 
increase  of  hydrostatic  head,  the  sinter  accumulation  encroached  upon  the  marsh;  at 
other  times  the  accumulation  of  sediment  encroached  upon  the  suiter. 

As  the  suiter  continued  to  build,  coincident  with  the  subsidence  and  sedimentation 
of  the  region,  the  same  excess  of  carbon  dioxide  in  the  ascending  waters  that  prevented 
a  deposition  of  carbonates  in  the  channel  below,  attacked  and  redissolved  the  bottom 
layers.  By  the  periodic  rapid  deposition  of  the  sinter  above  and  its  slow,  constant 
dissolution  below  by  the  carbonated,  saline  waters,  open  spaces  were  developed  that 
were  carried  upward,  hi  which  the  salt  was  deposited  from  ascending  solutions  that 
were  supersaturated  with  saline'  contents  by  the  release  of  pressure,  as  well  as  by 
evaporative  losses  these  waters  must  have  sustained  at  the  surface,  as  the  rapid  sinter 
accumulation  checked  the  flow  from  the  springs. 

Kennedy31  states: 

We  may  reasonably  suppose  that  the  deposits  carry  a  great  many  times  more  the 
quantity  of  saline  matter  than  calcic  matter  and  this,  as  well  as  the  more  ready  solu- 
bility of  the  salt,  would  give  the  salt  a  greater  preponderance  in  the  percolating  solu- 
tions and  under  these  conditions  it  is  probable  a  large  proportion  of  salt  had  reached 
the  depression  or  basin  in  which  it  was  deposited  before  the  less  soluble  lime  carbonate 
began  to  move.  Evidently  the  two  ingredients  reached  the  basin  together  in  unequal 
proportions  and  then,  due  to  this  inequality,  the  lime  remained  longer  in  solution 
than  the  salt.  Very  little  lime  occurs  intermingled  with  the  salt  but  considerable  salt 
remains  in  the  lime  or  its  gypsum  condition.  This  no  doubt  accounts  for  the  presence 
of  gypsum  above  the  salt. 

Several  factors  were  concerned  in  the  precipitation  or  deposition  of 
the  salt.  In  the  order  of  their  probable  importance,  they  may  be  stated 
as  follows: 


«•  Op.  ait.,  507,  508.  «  Op.  tit.,  58. 


W.   G.   MATTBSON  309 

1.  Deposition  and  precipitation  due  to  the  evaporative  effects  of 
expanding   gases   on   concentrated   brines   and   supersaturated   saline 
solutions. 

2.  Precipitation  caused  by  the  presence  of  a  common  ion. 

3.  Precipitation  due  to  chemical  reaction  between  brines  of  varying 
concentration  and  slightly  different  composition. 

4.  Deposition  and  precipitation  due  to  lowering  of  temperature. 

5.  Deposition  and  precipitation  due  to  lowering  of  pressure. 

6.  Deposition  and  precipitation  due  to  other  evaporative  effects  near 
or  at  the  surface. 

Opponents  of  the  secondary  origin  of  the  domal  materials  based  their 
arguments  on  the  vast  quantity  of  salt  known  to  underlie  these  domes, 
and  the  enormous  and  seemingly  improbable  quantity  of  brine  required 
to  yield  such  masses  through  the  processes  of  precipitation.  Rogers32 
sums  up  some  of  these  objections  as  follows: 

The  effect  of  decrease  in  temperature  and  pressure  on  the  solubility  of  salt  is  small. 
One  hundred  parts  of  water  can  carry  45  parts  of  sodium  chloride  in  solution  at  180°  C., 
39  parts  at  100°,  and  36  parts  at  15°.  If  it  be  assumed  that  the  solution  became  satu- 
rated and  started  to  rise  from  a  depth  of  7200  ft.,  where  its  temperature  would  be 
100°  C.,  it  would  lose  only  3  parts,  or  about  8  per  cent.,  of  its  total  load,  and  for  every 
ton  precipitated,  over  11  tons  must  have  escaped. 

The  escape  of  the  bulk  of  the  saturated  solution  is  not  explained.  No  smaller 
bedded  deposits  of  salt  from  evaporation  of  these  solutions  are  observed  in  the  vicinity 
of  the  domes.  As  some  of  the  domes  have  grown  within  recent  years  and  are  probably 
still  growing  today,  we  should  expect  to  find  great  volumes  of  saturated  salt  solutions 
issuing  from  them,  yet  only  minor  seeps  of  relatively  dilute  character  are  known. 

The  volume  of  ordinary  sea  water  required  to  produce  the  salt  would 
be  extremely  great.  Sixty  domes,  each  containing  only  the  quantity  of 
salt  already  blocked  out  at  Humble  (66  billion  tons)  require  4000  billion 
tons,  which  represents  the  complete  evaporation  of  about  25,000  cu.  mi. 
of  sea  water.  Assume  that  one-third  of  the  rocks  consist  of  material 
coarse  enough  to  allow  an  appreciable  movement  of  water  and  that  this 
material  has  a  porosity  of  30  per  cent.,  then  the  whole  section  has  an 
average  porosity  of  10  per  cent.  The  25,000  cu.  mi.  of  sea  water  would 
saturate  250,000  cu.  mi.  of  rock,  or  a  block  2  mi.  deep,  extending  from 
Matagorda,  Tex.,  to  Assumption,  La.,  and  stretching  from  the  coast 
northward  to  central  Arkansas  and  Oklahoma,  where  the  Paleozoic  rocks 
outcrop.  On  the  other  hand,  if  we  accept  Harris's  theory  of  deposition 
from  concentrated  brine,  enough  saturated  brine  to  fill  the  pores  in  an 
equal  block  of  strata  would  be  required. 

Any  legitimate  objection  raised  by  the  above  reasoning  has  been 
eliminated  by  the  recent  investigations  and  researches  of  Mills33  and 

32  Op.  c#.,  451. 

33  R.  Van  A.  Mills  and  R.  C.  Wells:  Evaporation  and  Concentration  of  Waters 
Associated  with  Petroleum  and  Natural  Gas.    U.  S.  Geol.  Survey  Butt.  693. 


310      SECONDAKT  INTRUSIVE  ORIGIN  OF  GULF  COASTAL  PLAIN  SALT  DOMES 

Wells.  They  recite  instances  where  gas  wells  in  the  Appalachian  field 
under  810  Ib.  rock  pressure  have  gone  "dead"  in  24  hr.,  and,  on  pulling 
tubing  and  cleaning  out  the  well,  4000  Ib.  of  salt  were  removed  after  which 
production  was  again  obtained.  The  deposition  of  barium  sulfate  and 
calcium  carbonate  in  wells  is  also  recorded  and  specific  attention  is  called 
to  the  banded  nature  of  these  deposits.  The  bands  look  much  like  what 
Rogers34  terms  stratification  planes  in  the  salt  core  at  Avery's  Island,  and 
suggest  the  probability  that  such  so-called  bedding  is  due  to  similar 
causes  and  the  contorted  nature  of  these  bands  is  the  result  of  slight, 
local,  differential  movements.  Mills  and  Wells35  note  the  greatly  de- 
creased solubility  of  salt  in  the  presence  of  a  common  ion  showing  that, 
whereas  a  solution  free  from  calcium  chloride  and  having  a  specific  gravity 
of  1.202  at  25°  C.  can  dissolve  and  contain  26.43  per  cent.,  by  weight,  of 
sodium  chloride,  when  calcium  chloride  is  added  up  to  24.58  per  cent,  by 
weight,  only  5.63  per  cent,  by  weight  of  sodium  chloride  remains  in 
solution.  These  investigators  likewise  show  that  a  cubic  meter  of  gas, 
confined  at  a  pressure  of  100  atmospheres  in  contact  with  a  saturated 
salt  solution  at  40°  C.,  in  expanding  to  atmospheric  pressure,  would 
evaporate  3800  gm.  of  water,  which  would  cause  the  precipitation  of  1400 
gm.  of  salt.  Continuing,  they  make  the  following  conclusions  :36 

Although  it  is  true  that  the  solubility  of  salt  decreases  with  falling  temperature, 
the  change  is  small.  The  amount  of  salt  that  will  precipitate  from  1  cu.  m.  of  satu- 
rated brine  on  cooling  from  60°  to  20°  C.  is  about  11  kg.  The  deposition  of  11  kg.  of 
salt  would  leave  883  kg.  of  water  saturated  with  317  kg.  of  salt  as  a  brine  taking 
no  part  in  the  process,  so  that  the  amount  of  brine  necessary  to  form  a  dome  by 
deposition  due  to  cooling  would  be  very  large.  Looked  at  in  another  way,  1  cu.  m. 
of  brine  could  deposit  11  kg.  of  salt  by  cooling  or  330  kg.  by  evaporation  (through 
expansion  of  gases). 

It  is  not  necessary  that  the  gases  escape  to  the  surface  in  order  to  cause  evapora- 
tion, for  in  deep-seated  strata,  under  certain  conditions,  especially  where  the  beds 
have  undergone  fissuring,  gas  may  flow  from  one  bed  where  the  pressure  is  higher  to 
another  bed  where  a  lower  pressure  prevails.  The  evaporative  effects  of  the  migrating 
gas  would,  under  these  conditions,  be  none  the  less  important.  The  deposition  of 
constituents  other  than  chlorides,  such  as  carbonates  or  sulfates,  might  be  caused  by 
evaporation,  so  as  to  produce  the  unusual  relations  sometimes  observed  in  salt  domes. 
It  also  seems  probable  that  where  the  salt  masses  are  associated  with  deposits  of 
calcium  sulfate  and  calcium  carbonate,  geochemical  processes  yielding  sodium  chloride, 
together  with  other  compounds,  have  been  brought  about  through  the  mixing  of 
solutions  that  have  different  properties  of  reaction  or  through  reactions  between  con- 
stituents of  certain  solutions  and  those  of  the  containing  rocks. 

Adequacy  of  Gas  Supply  to  Cause  Great  Salt  Deposition 

The  gases  necessary  to  produce  the  enormous  evaporative  effect^ 
noted  may  be  derived  from:  (1)  Dry  marsh  gases,  peat  and  lignitic  gases, 
derived  from  the  decay  of  swamp  matter  and  other  vegetation;  (2)  hydro- 


" Op.  cit.,  469.  "Op.  tit.,  73.  «•  Op.  cit,  92,  90 


W.    G.    MATTESON  311 

gen-sulfide  gases  resulting  from  the  oxidation  of  iron  pyrite;  (3)  gases 
developed  in  the  metamorphism  of  carbonaceous  shales  frequently  found 
associated  with  oil  and  gas  deposits. 

There  is  sufficient  evidence  of  gas  in  the  Gulf  coast  province  to 
indicate  that  the  quantity  demanded  for  the  great  evaporative  effects 
necessary  has  been,  and  probably  still  is,  present.  Thousands  of  seeps, 
emitting  marsh  and  hydrogen  sulfide  gases,  are  recorded  over  the  thou- 
sands of  square  miles  of  the  Gulf  province;  and  these  seepages  have  been 
in  operation  for  a  long  period.  The  10,000  ft.  (3040  m.)  of  Tertiary 
and  Quaternary  deposits  is  featured  by  vast  quantities  of  iron  pyrite, 
peat,  and  lignite  in  well-defined  beds  or  disseminated  throughout  the 
formations.  In  addition,  the  Yegua  formation  alone  has  developed  enor- 
mous quantities  of  gas  from  the  Rio  Grande  River  to  the  Louisiana  border 
and  beyond. 

Thus,  the  researches  of  Mills  and  Wells  have  eliminated  the  last 
barrier  to  the  acceptance  of  deposition  from  solution  as  the  origin  of  the 
salt  and  associated  materials.  The  deposition  of  the  greater  percentage 
of  salt  from  a  saturated  solution  due  to  the  evaporative  effects  of  expand- 
ing gases  has  been  proved  both  as  a  possibility  and  a  probability  and 
the  presence  of  sufficient  quantities  of  gas  for  the  purposes  in  view  has 
been  indicated.  Such  gases,  combined  with  the  five  other  factors  enum- 
erated, acting  on  a  continuous  supply  of  strong,  saturated  or  super- 
saturated brine  over  a  great  period  of  time,  could  unquestionably 
produce  the  enormous  salt  masses  observed  in  the  domes  of  the  Gulf 
coastal  plain  province. 

Adequate  Source  of  Supply  of  Salt  and  Limestone 

The  Quaternary  and  Tertiary  sediments  of  the  Gulf  coastal  plain 
province  have  an  estimated  thickness  of  10,000  ft.  (3040  m.)  with  8000 
to  10,000  ft.  of  underlying  Cretaceous  formations.  Thirty  to  forty  per 
cent,  of  the  Cretaceous  deposits  consist  of  limestones  and  the  remainder 
is  composed  of  marls,  shales,  and  sands.  Several  investigators  have 
called  attention  to  the  disseminated  saline  character  of  the  Cretaceous 
deposits.  In  this  connection,  Hill37  made  the  following  notation: 

The  fact  that  the  water  increases  in  temperature  and  salinity  is  conclusively 
proved  by  a  line  of  wells,  100  mi.  in  length,  between  Comanche  and  Marlin,  in  the 
lower  portion  of  the  Cretaceous  series.  The  same  stratum  which  furnishes  water  at 
both  places  outcrops  at  Comanche  and  supplies  good  potable  water  at  almost  every 
atmospheric  temperature.  At  Marlin,  100  mi.  eastward,  this  water  comes  from  a 
depth  of  3200  ft.,  has  a  temperature  of  nearly  140°  F.,  and  is  excessively  saline  and 
sulfurous. 

A  careful,  lithologic  examination  of  the  Tertiary  strata,  composed 
almost  entirely  of  unconsolidated  sands  and  clays,  reveals  numerous 

*7  Hill:  Op.  tit. 


312      SECONDARY  INTRUSIVE  ORIGIN  OF  GULF  COASTAL  PLAIN  SALT  DOMES 

horizons,  from  the  oldest  to  the  youngest,  containing  numerous  concre- 
tions and  nodules  of  limestone,  testifying  to  the  calcareous  and  alkaline 
character  of  the  sediments.  Even  greater  is  the  evidence  of  vast  quanti- 
ties of  saline  material,  disseminated  throughout  the  formations.  Investi- 
gators have  recorded  the  presence  of  hundreds  of  salines  and  salt  licks 
from  the  Cretaceous-Tertiary  contact  southward.  These  licks,  destroying 
all  vegetation  over  them  except  the  salt  grass,  are  featured  by  the  white 
crusts  formed  at  the  surface  in  a  dry  period  following  a  wet  spell,  when 
capillary  processes  and  evaporation  bring  the  saline  material  to  the  top 
of  the  ground.  Generally,  bare  spots  in  an  otherwise  grass-covered 
prairie  testify  to  their  presence.  No  better  evidence  of  the  widespread, 
disseminated,  saline  character  of  these  Tertiary  sediments  is  desired  than 
the  presence  of  these  salt  licks.  Kennedy38  early  called  attention  to  the 
saline  content  of  the  Yegua  formation  and,  in  a  more  recent  publication, 
made  the  following  statements:39 

The  Fleming  shales  carry  large  quantities  of  saline  and  other  mineralized  watei  s 
and  probably  such  waters  have  something  to  do  with  the  formation  of  the  mound. 
These  shales  also  carry  lime  plentifully  in  a  carbonate  form  as  well  as  gypsum.  .  . 
Carbonate  of  lime  goes  into  solution  when  associated  with  carbon  dioxide  in  alkaline 
solutions.  An  examination  of  the  analyses  of  the  soils,  subsoils,  clay,  acd  waters 
of  the  rivers  and  deep  wells  shows  the  presence  of  alkalies  in  considerable  quantity. 
The  lime  of  the  domal  materials  was  obtained  from  the  leaching  of  the  various  beds 
from  the  Upper  Cretaceous  to  the  Miocene  and  probably  Pliocene .  .  .  We  know 
that  most  of  our  Miocene  deposits  carry  large  percentages  of  salt,  carbonate  of  lime, 
and  organic  remains .  .  .  Moreover,  there  is  an  abundance  of  saline  matter  through- 
out the  Gulf  coast  Tertiaries  to  account  for  the  salt  found  in  these  mounds,  enor- 
mous as  it  is. 

Direct  field  observations  and  theoretical  considerations  present  con- 
clusive evidence  of  the  existence  of  conditions  favorable  to  the  deposition 
of  lime  and  salt.  DeGolyer,40  in  calling  attention  to  the  experiments  of 
Frank  K.  Cameron,  notes  that  calcium  bicarbonate  has  a  solubility  of 
0.06  gm.  per  li.  in  solutions  with  no  sodium  chloride,  a  solubility  of  0.101 
gm.  per  li.  in  a  solution  containing  39.62  gm.  of  sodium  chloride  per  liter, 
and  a  solubility  of  only  0.04  gm.  per  li.  in  a  solution  containing  267.6  gm. 
of  sodium  chloride  per  liter.  Thus  calcium  carbonate  is  less  soluble  in 
concentrated  brines  than  in  pure  water.  There  is  no  doubt  that  these 
conditions  obtained  during  the  deposition  of  the  mound  materials. 
The  high  alkaline  and  carbon  dioxide  content  of  the  hot,  ascending  brines, 
due  to  the  leaching  of  thousands  of  cubic  miles  of  soils,  rich  in  alkaline 
earths,  would  hold  the  lime  in  solution  until  near  the  surface,  when  the 

M  William  Kennedy :  A  Section  from  Terrell,  Kaufman  County,  to  Sabine  Pass 
on  the  Gulf  of  Mexico.  Third  Annual  Rept.  Geol.  Survey  of  Texas  (1891)  43. 

»  William  Kennedy:  Coastal  Salt  Domes.   Southwestern  Assn.  Pet.  Geol.  Bull.  1 

(1917)  54,  57. 

«  E.  L.  DeGolyer:  Origin  of  the  Cap  Rock  of  the  Gulf  Coast  Domes.  Econ.  Geol 

(1918)  13,  616. 


W.    G.   MATTESON  313 

escape  of  the  carbon  dioxide  and  the  supersaturated  saline  condition 
of  the  brine  would  cause  rapid  deposition  of  the  lime,  probably  in  part 
as  travertin.  In  discussing  the  rapidity  of  such  sinter  accumulation, 
Norton41  quotes  Geikie  as  follows: 

The  travertin  of  Tuscany  is  deposited  at  the  Baths  of  San  Vignone  at  the  rate  of  6 
in.  a  year,  at  San  Filippo  1  ft.  in  4  mo.  At  the  latter  locality,  it  has  piled  up  to  a 
depth  of  at  least  250  ft.,  forming  a  hill  1^  nri.  long  and  ^  mi.  broad.  Another  illus- 
tration of  the  rapidity  with  which  the  travertin  may  be  deposited  is  furnished  by  the 
Eocene  sinter  of  Sezanne,  Marne.  This  deposit  contains  hollow  casts  of  flowers  which 
fell  on  the  growing  sinter  and  were  crusted  over  with  it  before  they  had  time  to  wither. 

Norton42  refers  to  a  notation  by  Veatch  of  an  outcrop  of  gray, 
granular,  sandy  limestone,  containing  very  imperfect  plant  impressions 
at  Drakes's  Saline  and  to  Vaughn's  statement  that  near  Atlanta,  in 
Winn  Parish,  there  outcrops  a  hard,  blue  limestone  which  is  traversed 
by  minute  fissures  and  in  which  Veatch  found  impressions  of  dicotyle- 
donous leaves,  Norton  regarding  all  such  limestone  with  leaf  impressions 
as  non-marine  and  not  having  been  formed  in  the  ordinary  way.  The 
great  deposits  of  limestone  and  sinter  at  Winnfield,  La.,  have  already  been 
cited  and  Kennedy,43  in  1902,  called  attention  to  the  deposition  of 
calcium  carbonate  from  salt  springs  at  High  Island.  It  should  be  noted 
that  no  such  quantities  of  limestone  observed  capping  some  of  the 
coastal  plain  salt  domes  are  found  anywhere  associated  with  the  Euro- 
pean salt  domes — strong  testimony  of  different  conditions  of  origin  and 
formation. 

Frank  K.  Cameron,44  during  his  soil  researches  for  the  Government, 
conducted  a  series  of  experiments  which  proved  that  beyond  a  certain 
point  an  increase  in  the  sodium-chloride  content  of  salt  brines  caused  a 
decrease  in  the  solubility  of  gypsum.  On  this  basis,  DeGolyer  suggests 
that  the  cap  rock  was  precipitated  from  solution  by  circulating  cal- 
cium-sulf ate-bearing  waters  coming  in  direct  contact  with  the  salt  plug 
after  the  formation  of  the  latter,  the  salt  content  of  the  calcium-sulfate 
waters  being  thereby  increased  to  the  point  demonstrated  in  Cameron's 
experiments  as  necessary  to  cause  deposition.  The  vital  defect  in  this 
process  is  the  formation  of  a  protective  covering  of  gypsum  cap  rock 
over  the  top  of  the  salt  in  a  short  time,  after  which  the  circulating  calcium- 
sulfate  waters  would  have  difficulty  in  coming  in  direct  contact  with  the 
salt  core  and  effecting  the  necessary  concentration  to  cause  the  precipi- 
tation of  sufficient  gypsum  to  account  for  the  masses  300  to  1000  ft. 
(91  to  304  m.)  thick  now  overlying  the  salt  in  the  various  domes. 

«  Norton :  Op.  tit,  510. 
«0p.  tit.,  507. 

«  C.  W.  Hayes  and  William  Kennedy:  U.  S.  Geol.  Survey  Bull  212. 
44  Frank  K.  Cameron:  Solubility  of  Gypsum  in  Aqueous  Solutions  of  Sodium 
Chloride.    U.  S.  Dept.  of  Agriculture,  Division  of  Soils  No.  18,  25-45. 


314      SECONDARY  INTRUSIVE  ORIGIN  OF  GULF  COASTAL  PLAIN  SALT  DOMES 

Rogers45  also  questions  this  theory  due  to  the  fact  that  examination  of  the 
analyses  of  waters  in  the  Gulf  coast  province  shows  them  to  be  surpris- 
ingly low  in  calcium  sulfate. 

In  supporting  the  primary  intrusive  origin  of  the  salt  domes,  Wash- 
burne46  recently  gave  several  reasons  why  the  formation  of  the  salt  cores 
through  deposition  from  supersaturated  brines  is  impossible:  That  the 
escape  of  gas  at  the  locus  of  any  dome  in  sufficient  quantity  to  account 
for  the  deposition  of  salt  through  the  evaporative  action  of  expanding  gas 
would  keep  the  vertical  channels  so  free  and  open  that  there  would  be  no 
accumulation  of  oil  and  gas  at  these  places;  also,  that  since  the  salt  cores 
are  at  least  a  few  thousand  feet  in  vertical  dimension,  they 'cut  so  many 
water-bearing  sands  that  the  possibility  of  ascending,  saturated  solutions 
maintaining  sufficient  concentration  to  effect  precipitation  is  doubtful 
due  to  the  mingling  of  fresh  artesian  waters  or  dilute  brines  from  these 
water-bearing  sands  with  the  saline-bearing  brines.  He  even  states  that 
the  cutting  of  fresh-water  sands  by  these  vertical  channels  would  permit 
such  meteoric  waters  to  enter  the  channels  and  not  only  prevent  deposi- 
tion of  the  salt  but  would  probably  dissolve  any  salt  already  deposited. 

Washburne's  contentions  can  be  easily  eliminated  from  the  problem. 
The  oil  and  gas  did  not  accumulate  on  and  around  these  salt  domes  in  all 
probability  until  some  time  after  the  core  was  formed,  so  that  free  and 
open  channels  would  in  no  way  affect  the  problem  of  petroleum  accumula- 
tion. Neither  would  these  vertical  channels  cut  fresh -water-bearing 
sands  capable  of  releasing  artesian  flows  that  would  dilute  the  ascending 
solutions  of  concentrated  brines  beyond  the  point  where  precipitation  of 
salt  and  other  materials  would  be  possible.  Meteoric  waters  are  seldom 
found  in  the  Gulf  coastal  plain  province  below  1500  ft.  (457  m.)  and  all 
water-bearing  sands  to  this  depth  immediately  adjacent  to  these  domes 
are  lenticular  in  character,  and,  therefore,  strong  artesian  flows  are  not 
observed.  Even  if  such  artesian  flows  occurred,  their  volume  would  be 
so  small,  in  comparison  with  the  volume  of  saturated  brine  ascending 
from  a  depth  of  5000  to  20,000  ft.  under  several  thousand  feet  of  hydro- 
static head,  that  such  fresh  waters  could  have  little  quantitative  effect. 
Mills  and  Wells47  have  shown  that  these  dilute,  meteoric  waters  often 
contain  calcium  chloride,  which  decreases  the  solubility  and  causes  the 
deposition  of  sodium  chloride.  These  investigators  also  quote  instances 
where  fresh  water,  introduced  into  gas  wells  plugged  by  salt,  failed  to 
dissolve  materially  this  substance. 

The  lenticular  nature  of  the  water-bearing  sands  is  acknowledged  by 
Washburne  who  states,  however,  that  there  are  some  sands  of  widespread 

41 G.  Sherburne  Rogers :  Intrusive  Origin  of  the  Gulf  Coast  Salt  Domes — Discus- 
sion. Econ.  Geol.  (1919)  14,  179. 

*•  Chester  W.  Washburne:  Oil-field  Brines.    See  page  269. 
«  Op.  cit.,  73. 


W.    G.    MATTESON  315 

coDtinuity  which  outcrop  much  farther  to  the  north  and  which  would 
answer  his  purpose.  Hill  has  shown  that  fresh  waters  entering  such 
sands  at  their  outcrop  become  highly  saline  in  character  in  a  relatively 
short  distance  from  the  outcrop.  Washburne  suggests  two  additional 
reasons  that  might  prevent  meteoric  waters  from  entering  the  open 
channels  along  which  the  supersaturated  brines  might  be  ascending: 
First,  the  pores  of  the  sands  next  to  the  fissures  might  be  clogged  with 
salts;  Mills  has  shown  that  this  actually  happens.  Second,  the  gas 
pressure  may  keep  the  water  from  entering  the  fissures.  Harris48  adds  a 
third  reason:  "The  compacting  and  slickensiding  of  the  deposits  about 
the  lower  main  part  of  the  core  would  tend  to  debar  the  close  approach  of 
fresh  waters,  and  yet  leave  a  suture  line  for  the  ascension  of  brines."  Like- 
wise the  importance  of  explaining  logically  the  presence  of  the  limestone 
in  any  theory  accounting  for  these  domal  materials  is  conceded  by 
Washburne,  who  abandons  such  explanation  as  hopeless,  however. 

Alteration  of  Limestone  to  Gypsum 

The  limestone  of  the  salt  domes  is  found  in  irregular  masses  through- 
out the  gypsum,  and  occasionally  as  a  cap  rock  of  limited  thickness  on 
top  of  the  gypsum.  When  a  cap  rock,  it  varies  in  thickness  from  a  few 
to  a  hundred  feet,  and  occasionally  more,  and  is  decidedly  sandy  in 
character,  which  may  account  in  part  for  its  resistance  to  alteration  and 
its  capacity  to  hold  oil.  Spindletop  and  Humble  have  a  typical  lime- 
stone cap  rock.  Considerable  thicknesses  of  massive  gypsum,  however, 
almost  always  overlie  the  salt,  throughout  which  limestone  is  always 
found,  bearing  such  relationship  to  it  as  would  be  expected  as  a  result  of 
alteration  and  replacement.  Cores  from  Sulphur  Mine,  La.,  show  the 
cap  rock  to  be  composed  of  gypsum  and  limestone  with  cavities  filled 
by  crystalline  sulfur.  At  Damon  Mound,  according  to  Kennedy,49 

The  line  of  separation  between  the  limestone  and  gypsum  is  an  extremely  irregular 
one.  In  places,  large  blocks  of  gypsum  extend  many  feet  into  the  limestone  and  in 
others  the  lime  descends  into  the  gypsum.  Although  the  massive  beds  are  designated 
as  gypsum,  they  are  by  no  means  wholly  sulfate  of  lime.  Tests  made  of  cores  brought 
out  of  a  number  of  wells  show  them  to  be  a  mixture  of  sulfate  and  carbonate  with  the 
carbonate  usually  in  contact  with  the  sulfate. 

Examination  of  the  cores  at  Bryan  Heights  shows  the  gypsum  to 
contain  numerous,  irregular  masses  and  nodules  of  limestone  and  oc- 
casional barite.  The  limestone  is  soft  and  porous  and  both  the  limestone 
and  gypsum  contain  cavities  filled  with  crystalline  sulfur.  Enormous 
quantities  of  hot  waters  containing  free  sulfuric  acid  and  hydrogen  sul- 
fide  are  observed  at  this  dome.  Hot  water,  carrying  free  sulfuric  acid, 
and  great  volumes  of  hydrogen  sulfide  are  known  at  Sulphur  Mine,  La. 

«  Harris:  Op.  tit.  «  Op.  tit.  (Assn.  Pet.  Geol.)  50. 


316      SECONDARY  INTRUSIVE  ORIGIN  OP  GULF  COASTAL  PLAIN  SALT  DOMES 

There  is  little  question  that  the  sulfur  is  the  result  of  secondary  action 
and  has  been  deposited  from  solution. 

Constantly  accumulating  data  present  convincing  evidence  that  the 
gypsum  of  these  salt  domes  has  resulted  largely  through  the  alteration  of 
limestone  due  to  the  action  of  waters  carrying  free  sulfuric  acid  and 
hydrogen  sulfide.  The  writer  has  examined  many  cuttings  from  various 
formations  of  the  Gulf  coastal  plain  province  and  has  been  impressed  with 
the  quantity  of  disseminated  pyrite  present.  Sour  springs  and  waters 
carrying  free  sulfuric  acid  are  observed  in  connection  with  these  domes 
today.  Hill50  has  mentioned  the  sulfurous  character  of  the  Cretaceous 
waters  at  Marlin.  Hydrogen  sulfide,  in  great  quantity,  is  also  of  general 
record  throughout  the  coastal  plain  region. 

There  is  absolutely  no  question  of  the  superabundance  of  sulfides 
which  may,  through  oxidation,  supply  vast  quantities  of  acid-bearing 
waters,  suitable  in  character  to  convert  the  limestone  into  gypsum.  One 
is  impressed  with  the  correctness  of  this  conclusion  when  recalling  that 
investigators  of  international  repute  have  shown  that  massive  gypsum,  so 
extensive  and  in  such  great  bodies  as  observed  in  connection  with  these 
coastal  domes,  has  been  formed  generally  through  the  alteration  of 
limestones.  Grabau51  agrees  with  I)ana  that  the  gypsum  masses  of  the 
Salina  formation  of  New  York  result  from  the  alteration  of  limestones  by 
acid-sulfate  waters,  which  abound  in  the  formation  and  which  have  re- 
sulted from  the  oxidation  of  iron  pyrites  in  the  rock.  He  adds,  "the 
occurrence  of  gypsum  in  the  dolomites  overlying  the  salts  at  Goderich, 
Canada,  is  probably  explained  in  a  similar  manner  and  the  gypsum 
deposits  of  Nova  Scotia  have  been  attributed  to  the  action  of  sulfuric 
acids  on  marine  limestones."  Kennedy52  states  that  "at  Damon  Mound, 
the  gypsum  has  the  appearance  of  being  the  altered  end  of  the  massive 
limestone  beds  found  at  the  southern  end  of  the  mound.  Two  limestone 
beds  having  a  thickness  of  70  and  650  ft.,  respectively,  are  reported  from 
the  southern  end,  lying  between  260  and  1180  ft.;  %  mi.  north,  the  gyp- 
sum beds  are  378  and  409  ft.  thick  with  30  ft.  of  sulfur  and  sand  between." 

Of  course  there  is  the  possibility  that  the  gypsum  has  been  deposited 
from  the  same  brines  carrying  the  salt.  Attention  has  already  been 
called  to  DeGolyer's  statements  that  the  solubility  of  gypsum  in  aqueous 
solutions  decreases  with  a  constantly  increasing  concentration  of  sodium 
chloride.  Harris  also  points  out  that  the  solubility  of  gypsum  in  aqueous 
solutions  is  rapidly  decreased  when  the  salt  content  is  reduced  below  14 
per  cent.  The  writer  has  recently  obtained  data  at  High  Island  which 
suggest  that  the  precipitation  of  salt  from  saturated  to  supersaturated 

"Op.  tit. 

"  A.  W.  Grabau:  "Principles  of  Salt  Deposition"     McGraw-Hill. 

11  Coastal  Salt  Domes.    Southwestern  Assn.  Pet.  Geol.  Bull.  1,  50. 


W.    G.    MATTESON  317 

brines  is  so  complete  that  such  dilution,  favorable  to  the  subsequent 
precipitation  of  gypsum,  is  actually  obtained. 

However,  the  cavernous  condition  of  the  gypsum,  its  spongy  character 
in  many  instances,  and  the  presence  of  cavities  lined  with  sulfur  crystals, 
point  to  the  action  of  waters,  and  the  presence  of  waters  of  the  necessary 
character  has  been  recorded.  These  facts  in  connection  with  the  dis- 
seminated condition  of  the  limestone  in  and  throughout  the  gypsum, 
both  as  small  grains  and  irregular  masses  of  varying  size  and  indefinite 
outline,  and  the  irregular  projection  of  gypsum  into  limestone  and  lime- 
stone into  gypsum  where  a  definite  limestone  cap  rock  is  observed,  point 
strongly  to  alteration  and  replacement  processes;  in  fact,  no  other  theory 
could  logically  explain  such  conditions  and  association. 

Initial  Period  of  Movement  and  Uplift 

Abundant  evidence  exists  that  the  salt  domes  have  been  subjected 
to  more  than  one  period  of  movement.  Deussen53  states  that  the 
evidence  is  plain  that  the  growth  of  the  salt  core  is  not  one  growth,  but 
the  result  of  several  movements  at  different  times,  as  shown  in  the 
Anderson  County  domes.  The  coastal  domes  also  have  two  distinct 
movements. 

The  initial  movement  probably  occurred  contemporaneously  with 
the  formation  of  the  domal  core  and  continued  for  some  time  thereafter. 
Three  factors  were  involved  in  this  uplift;  namely,  the  increase  in  volume 
resulting  from  the  alteration  of  limestone  to  gypsum,  the  forces  of  growing 
salt  crystals,  and  the  general  subsidence  of  the  region. 

An  increase  in  volume  of  32  to  50  per  cent,  occurs  when  limestone  is 
converted  into  gypsum.  Since  the  gypsum  shows  a  varying  thickness 
of  a  few  to  several  hundred  feet,  and  since  part  of  the  gypsum  has  prob- 
ably been  removed  by  erosion  in  some  instances,  it  can  be  estimated 
conservatively  that  an  uplift  or  doming  of  200  to  300  ft.  would  result 
from  this  factor  alone.  That  the  forces  of  growing  crystals  would  also 
be  a  factor  in  doming  is  evident  but  it  is  quite  probable  that  the  extent 
of  uplift  due  to  this  cause  alone  has  been  greatly  exaggerated. 

There  is  slight  doubt  that  the  domal  materials  were  originally  depos- 
ited relatively  near  the  surface.  The  thickening  of  the  same  formations 
away  from  the  domes,  which  can  hardly  be  accounted  for  except  that  the 
first  two  factors  of  uplift  were  probably  sufficiently  active  to  cause  uplift, 
which  prevented  deposition  of  sediments  to  some  extent  on  top  of  the 
dome  while  subsidence  of  the  immediately  adjacent  areas  permitted  con- 
tinuous sedimentation  and  deposition  and  at  least  apparently  increased 
the  extent  of  the  initial  uplift,  is  direct  evidence  of  near  surface  precipita- 
tion. Conditions  observed  at  many  of  these  domes  indicate  an  uplift 

63  Op.  tit.,  84. 


318      SECONDARY  INTRUSIVE  ORIGIN  OF  GULF  COASTAL  PLAIN  SALT  DOMES 

of  1500  to  2500  ft.  (457  to  762  m.)  yet  nothing  in  the  character  of  the  erogenic 
movements  affecting  the  coastal  plain  province  points  to  forces  capable 
of  producing  such  displacement  being  generally  active.  It  therefore  seems 
probable  that  part  of  this  uplift  is  the  result  of  nicely  balanced  conditions 
of  sedimentation  wherein  initial  forces  of  uplift  were  sufficient  to  keep 
pace  or  overcome  the  general  subsidence  of  the  region;  this  resulted  in 
formations  near  the  domes  being  considerably  elevated  compared  with 
the  same  formations  away  from  the  domes. 

Recently  the  writer  made  an  examination  at  High  Island.  On  the 
south  side,  an  area  of  one  or  two  acres  has  been  designated  as  the  "  trem- 
bling marshes/'  because  the  crust,  when  traversed,  would  shake  or  tremble 
over  a  considerable  distance  in  a  manner  similar  to  the  shaking  of  quick- 
sand. Eighteen  years  ago  this  area  was  a  slight  depression  in  which 
animals  would  bog;  today,  it  is  a  mound,  about  3  ft.  higher  than  the 
surrounding  territory,  composed  of  crystals  of  salt.  Salt  is  being  depos- 
ited there  by  springs  and  the  run-off,  after  deposition,  is  much  less  saline 
than  ordinary  ocean  water.  The  writer  regards  this  evidence  as  most 
important.  Kennedy54  records  the  deposition  of  carbonate  of  lime  from 
springs  on  the  west  side  of  the  Island  together  with  the  salt.  Is  not  this 
an  illustration  of  the  processes  which  resulted  in  the  formation  of  the  domal 
materials  and  caused  in  part  the  initial  uplift? 

Subsequent  Periods  of  Movement  and  Uplift 

The  formation  of  the  domal  materials  and  the  initial  period  of  uplift 
in  the  Texas-Louisiana  coastal  plain  province  was  followed  by  general 
subsidence  of  the  entire  region  and  a  long  period  of  sedimentation. 
During  this  time,  minor  movements  of  uplift  might  have  occurred  but 
on  such  a  small  scale  as  to  be  hardly  noticeable. 

Subsequently  a  series*  of  movements  and  uplifts  occurred  as  the 
direct  result  of  isostatic  readjustments  and  the  action  of  orogenic  forces 
of  some  magnitude.  These  forces  acted  along  old  fault  planes  and  other 
lines  of  weakness  and  undoubtedly  were  accompanied  by  considerable 
lateral  thrust.  As  a  result,  the  salt  cores  were  thrust  upwards  and 
intruded  into  the  overlying  strata.  The  entire  period  of  movement  was 
gradual  and  probably  extended  over  a  considerable  time  interval.  The 
direct  result  was  the  fissuring  of  the  cap  rock,  the  possible  production  on 
a  small  scale  of  plications  within  the  main  salt  mass,  the  possible  recrys- 
tallization  of  the  salt,  and  the  production  of  cross  and  radial  faulting 
around  the  dome.  It  was  these  subsequent  periods  of  uplift  which  pro- 
duced the  abrupt  upturning  of  the  strata  as  well  as  the  shearing  and 
piercing  of  the  same  now  observed  around  these  salt  cores.  The  com- 
bined uplift  undoubtedly  produced  marked  surface  doming.  During 

"Hayes  and  Kennedy:  U.  S.  Geol.  Survey  Bull.  212. 


W.    G.    MATTESON  319 

this  period,  erosion  was  again  active  and  continued  some  time  thereafter. 
Subsequently,  subsidence  occurred  and  recurred,  and  sedimentation  was 
resumed  on  such  a  scale  as  to  eliminate  completely  the  remaining  topo- 
graphic features  of  these  domes.  These  subsequent  periods  of  uplift 
varied  for  different  series  of  domes  but  occurred  at  various  intervals  from 
the  end  of  the  Cretaceous  era  to  the  present  time.  In  the  case  of  the 
commercially  important  oil-bearing  domes  immediately  adjacent  to  the 
present  Gulf  coast,  the  major  portion  of  the  subsequent  uplift  occurred 
near  the  end  of  the  Miocene  and  into  Pliocene  time  as  we  find  the  Miocene 
formations  pierced  and  deformed  with  the  domal  materials  often  intruded 
into  the  overlying  Pliocene,  which  has  been  steeply  arched. 

During  the  subsidence  that  followed,  Beaumont  clays  of  Pleistocene 
age  were  deposited  over  this  area,  completely  obscuring  the  topographic 
features  of  these  domes.  Another  period  of  gradual  uplift  then  began 
and  has  continued  up  to  the  present  time;  it  has  been  general  in  char- 
acter and  is  still  in  its  early  stages.  Its  important  significance  has  been 
the  development  of  slight  mounds,  hills,  or  ridges  at  the  loci  of  domes  in 
a  number  of  instances  where  the  forces  have  been  locally  more  intense 
and  especially  where  the  domal  materials  are  close  to  the  surface.  At 
points  where  the  domal  materials  are  deep  lying,  local  mounds  or  ridges 
due  to  uplift  are  generally  absent,  suggesting  that  the  forces  of  uplift 
have  so  far  been  absorbed  by  the  un consolidated  overlying  material 
without  deformation.  Erosion  may  account  for  the  absence  of  mounds 
and  ridges  in  some  instances.  This  topographic  expression  has  been 
one  of  the  most  reliable  characteristics  in  determining  the  locus  of  a 
salt  dome  and  domes  are  now  classified  in  the  field  according  to  topog- 
raphy, as: 

Domes  of  the  first  class  with  definite,  characteristic,  topographic 
expression  in  the  form  of  low,  roughly  circular  to  elliptic  mounds  or 
ridges,  rising  10  to  80  ft.  (3  to  24  m.)  abruptly  above  the  adjacent  prairie, 
as  illustrated  by  Damon  Mound,  Hull,  and  High  Island. 

Domes  of  the  second  class  with  slight  topographic  expression  in  the 
form  of  low,  roughly  circular  to  elliptic  mounds  or  ridges,  rising  2  to  10  ft. 
(0.6  to  3  m.)  somewhat  abruptly  above  the  adjacent  coastal  prairie,  as 
illustrated  by  Spindletop,  North  Dayton,  etc. 

Domes  of  the  third  class  with  no  domal  or  ridge  topography  but  occasion- 
ally with  sunken  depressions,  featuring  the  locus  of  the  salt  core,  as 
illustrated  by  Goose  Creek,  Edgerly,  or  South  Dayton. 

OIL  ACCUMULATION 

The  oil  associated  with  those  salt  domes  where  commercial  production 
has  been  obtained  is  of  Tertiary  origin.  This  conclusion  is  based  on  the 
grade  of  oil,  the  character  of  the  accumulation,  and  the  fact  that  the 


320      SECONDARY  INTRUSIVE  ORIGIN  OF  GULF  COASTAL  PLAIN  SALT  DOMES 

Tertiary  formations  are  petroliferous.  The  oil  of  the  Texas-Louisiana 
coastal  plain  has  an  asphalt  base,  whereas  the  great  percentage  of  oil 
obtained  from  the  Cretaceous  formations  in  this  province  is  largely  of  a 
paraffine  base,  while  oil  from  the  Pennsylvania  horizons  is  practically 
always  of  paraffine  character. 

On  90  per  cent,  of  the  producing  domes,  the  oil  is  obtained  from  the 
east,  southeast,  south,  or  southwest  sides.  As  this  is  the  side  corre- 
sponding to  the  normal  dip  of  the  formations  and  is  generally  the  side  of 
gentlest  dip,  this  fact  is  strong  evidence  of  the  Tertiary  origin  of  the  oil. 
If  the  oil  came  from  the  underlying  Cretaceous  and  Penijsylvanian 
formations,  migrating  upward  through  the  same  channels  with  the  saline 
brines,  the  oil  should  be  found  as  often  on  the  northern  and  north- 
western sides  of  the  domes  as  on  the  normal  sides. 

Data  gathered  point  to  the  Fleming  clays  of  Upper  Miocene  age 
as  the  original  source  of  the  oil.  These  clays  are  bituminous  in  character 
in  their  seaward,  marine  phase  underlying  the  present  area  adjacent  to 
the  Gulf  shore  line.  Oil  in  considerable  quantity  has  been  found  only  in 
regions  underlain  by  marine  Fleming  clays.  Tests  west  of  the  Colorado 
River  in  Texas,  where  the  equivalent  of  the  Fleming  clays  is  a  fresh-water 
deposit,  have  failed  to  find  oil  in  commercial  quantity. 

In  discussing  the  Humble  oil  field,  Deussen65  describes  the  oil  there 
as  originating  in  the  Yegua  clays  and  migrating  upwards  into  the  over- 
lying Oligocene  sands.  The  fossil  evidence  that  he  has  presented, 
though,  appears  open  to  question,  and  the  failure  of  the  Yegua  to  yield 
commercial  oil  from  hundreds  of  tests  that  have  penetrated  this  formation 
adds  to  the  difficulty  of  accepting  Deussen 's  conclusions  without  more 
data.  However,  the  Yegua,  Cook  Mountain,  and  Mt.  Selman  formations 
of  Eocene  age  are  partly  or  entirely  marine  in  character,  and  have 
exhibited  bituminous  phases.  The  Yegua  has  yielded  dry  gas  in  great 
quantity  and  numerous  oil  showings  up  to  1  or  2  bbl.  wells.  Although 
general  conditions  would  indicate  that  these  formations  have  oil-produc- 
ing possibilities,  the  universal  failure  of  numerous  wells  penetrating  these 
formations  where  structural  conditions  are  known  to  have  been  favorable 
is  discouraging. 

CONCLUSIONS 

The  intrusive  origin  of  the  Gulf  coastal  plain  salt  domes,  which 
postulates  that  the  salt  is  of  primary  origin  and  that  its  configuration, 
character,  and  position  are  due  primarily  to  intrusion  en  masse  from 
bedded  deposits  below,  is  untenable,  as  the  fundamental  principles 
constituting  the  basis  for  this  theory  are  not  substantiated  by  data 
gathered  from  exhaustive  detailed  field  examinations.  Since  the  theory 

"  Op.  tit.,  73. 


W.    G.    MATTBSON  321 

was  first  proposed,  numerous  deep  tests  have  penetrated  the  formations 
in  which  conditions  were  most  favorable  for  the  development  of  beds  of 
salt  but  no  such  beds  have  been  encountered  over  a  wide  area. 

The  analogy  between  the  European  and  American  domes,  which  has 
been  used  to  establish  similar  modes  of  origin,  is  one  of  form  only  and  is 
more  apparent  than  real.  Details,  fundamental  in  character,  indicate 
that  these  domes  must  have  had  a  widely  different  origin.  Bedded 
salt  deposits  of  great  thickness  and  extent  are  known  to  underlie  great 
areas  in  northwestern  Europe.  The  salt  cores  there  have  brought  up 
great  blocks  of  Permian,  Cretaceous,  Triassic,  and  Jurassic  strata  that 
normally  occur  at  great  depths;  the  salt  masses  contain  numerous  inclu- 
sions of  silt,  clays,  sandstones  of  the  typical  bedded  variety,  alternating 
beds  of  anhydrite,  limestone,  and  gypsum,  while  analysis  of  the  salt 
shows  the  presence  of  potassium  and  other  salts  typical  of  original 
bedded  deposits.  The  gypsum  and  limestone  cap  rock  of  the  American 
domes  is  much  thicker.  The  orogenic  forces  in  the  European  area  have 
been  most  intense  and,  with  the  geosynclinal  structure  of  the  region, 
have  undoubtedly  been  of  sufficient  magnitude  to  produce  the  results 
observed.  No  bedded  deposits  of  salt  have  been  found;  no  blocks  of 
deep-lying  strata  have  been  upthrust  into  younger  strata,  no  inclusions 
of  bedded  formations,  silts,  clays,  etc.,  nor  of  anhydrite,  limestone, 
potassium  and  allied  salts  are  generally  observed  in  the  American  domes; 
the  greater  portion  of  the  salt  shows  a  purity  that  can  be  logically  ex- 
plained only  by  precipitation  from  solution,  definite  in  chemical  composi- 
tion and  subjected  to  uniform  conditions  of  chemical  reaction.  The 
weight  of  the  overlying  strata  and  such  orogenic  forces  as  were  operative 
in  the  Texas-Louisiana  region  are  insufficient  to  bring  the  salt  cores  to 
their  present  position  from  depths  of  10,000  to  20,000  ft.  through  intru- 
sion en  masse. 

The  secondary  intrusive  origin  differs  from  the  previous  theory  in 
that  intrusion  of  the  domal  materials  en  masse  is  only  one  of  the  several 
factors  accounting  for  the  present  position  of  the  salt  cores  and  struc- 
tural deformation  produced,  the  domal  materials  being  first  regarded  as 
secondary  products,  deposited  relatively  near  the  surface  directly  from 
solutions  of  secondary  origin  and  character.  This  theory  is  based 
on  fundamental  details  observed  in  the  field;  it  is  in  conformance  with 
various  processes  still  observed  in  operation  in  and  around  these  domes; 
it  satisfies  every  detail  in  occurrence,  character,  and  shape  of  the  dome 
and  domal  materials,  and  their  relative  positions,  and  offers  a  satisfac- 
tory explanation  of  the  formation  of  the  cap  rock,  which  the  European 
theory  fails  to  do. 

This  secondary  intrusive  origin  theory  is  a  combination  of  several 
theories.  The  writer  has  taken  the  acceptable  portions  of  such  theories 
and,  from  data  gained  in  several  years  of  detailed  field  investigation, 

VOL.  LXV. — 21. 


322      SECONDARY  INTRUSIVE  ORIGIN  OF  GULF  COASTAL  PLAIN  SALT  DOMES 

has  supplied  the  connecting  evidence  necessary  to  mold  the  facts  and 
principles  into  a  concrete,  coherent  expression  or  explanation  of  the 
mode  of  origin,  in  such  a  way  as  to  eliminate  apparently  the  objections 
and  shortcomings  of  previous  statements  on  this  subject,  to  account 
for  chemical,  stratigraphic  and  structural  conditions,  and  to  satisfy  all 
observations  of  fact  recorded  in  the  fifty  odd  years  of  investigation  of 
these  domes.  The  Gulf  coastal  plain  province  is  one  of  the  most  difficult 
areas  to  analyze  geologically.  Each  dome  exhibits  certain  peculiarities 
so  that  extensive  data  become  essential  before  general  deductions  can  be 
made  and  theories  propounded  and  data  of  this  nature  can  be  accumu- 
lated only  by  careful,  diligent,  and  exhaustive  investigation  and  study 
on  the  part  of  numerous  geologists. 

If  the  secondary  intrusive  theory  of  origin  should  be  generally 
accepted,  it  should  be  remembered  that  such  a  theory  has  been  made 
possible  only  by  the  investigations  of  Lucas,  Kennedy,  Hill,  Dumble, 
Veatch,  Rogers,  and  Lee  Hager;  the  researches  of  Harris,  Norton,  Mills, 
Wells,  and  Washburne;  the  intelligent  and  constructive  criticism  of 
Rogers,  Woodruff,  and  others;  and  the  able  observations  of  Deussen 
and  DeGolyer.  To  these  geologists  especially,  and  to  many  others, 
credit  is  due  for  whatever  intelligent  understanding  we  possess  of  these 
peculiar  structural  entities,  and  of  this  the  writerjias  ever  been  mind- 
ful and  appreciative,  not  only  in  the  present  discussion  but  in  the 
years  of  personal  field  observation  conducted  with  a  similar^object 
in  view. 

DISCUSSION 

EUGENE  COSTE,  *  Calgary,  Alberta. — The  author 's  argument  is  weak 
in  that  he  attributes  the  enormous  masses  of  secondary  salts,  liquid 
hydrocarbons,  and  natural  gas  and  sulfuret  of  hydrogen  found  under 
the  domes  to  the  leaching  of  sediments.  It  is  absolutely  impossible  to 
admit  that  these  large  quantities  of  salt,  limestone,  silica,  sulfur,  sulfuret 
of  hydrogen,  and  gaseous  and  liquid  hydrocarbons  have  been  leached  out 
of  the  sediments  in  which  these  vertical  chimneys  of  secondary  products, 
known  as  salt  domes,  are  found.  It  is  just  as  untenable  to  believe  that 
as  it  is  to  believe  that  the  salt  masses  under  the  domes  are  derived  from 
big  beds  of  salt  in  the  lower  rocks,  which  it  has  been  proved  do  not  exist. 
The  circulation  of  meteoric  waters  in  the  sediments  takes  place  only  in  a 
few  porous  beds,  mostly  sandstones,  and  the  great  quantities  of  salt, 
sulfur,  and  other  products  mentioned  cannot  possibly  come  from  such  a 
source. 

*  President  and  Managing  Director,  The  Canadian  Western  Natural  Gas,  Light, 
Heat  and  Power  Co.,  Ltd. 


DISCUSSION  323 

We  will,  therefore,  have  to  return  to  the  solfataric  volcanic  view 
regarding  the  formation  of  these  salt  domes  that  I  advocated  before  this 
Institute66  about  17  years  ago.  We  know  that  all  through  that  district 
and  extending  south  to  Mexico  and  beyond  there  have  been  orogenic 
movements  at  different  geologic  periods  and  some  in  recent  time.  These 
have  resulted,  in  Texas  and  Louisiana,  in  great  deep  faults,  hundreds  of 
miles  long,  from  which  at  separate  points  along  their  course  gaseous  and 
liquid  solfataric  or  juvenile  emanations  have  come  up  from  the  interior. 
The  faults  are  miles  deep  and  have  brought  up  these  gaseous  and  hot 
waters  from  great  depth;  in  fact,  from  the  volcanic  magma  below.  This 
is  clearly  the  origin  of  all  of  the  secondary  products  under  the  salt  domes; 
and  in  some  of  the  domes  in  Texas  and  Louisiana,  as  well  as  in  Mexico, 
many  of  the  salt  waters  and  oils  are  still  at  high  temperature. 

We  cannot  imagine  that  the  great  masses  of  sulfur  in  Calcasieu 
parish,  Louisiana,  for  instance,  can  come  from  the  leaching  of  sediments, 
or  that  the  natural  gas  can  come  from  beds  of  carbonaceous  shale  that 
have  not  been  distilled  and  exist  in  the  sediments  as  undistilled  shales. 
Such  sediments  will  not  give  these  products  at  all,  especially  in  anything 
like  the  enormous  quantities,  recognized  by  the  author,  it  is  necessary 
to  admit  must  have  come  up  these  chimneys,  or  domes,  to  help  produce 
such  huge  deposits  of  salts,  etc.  by  the  concentration  of  brines  by  evapo- 
ration. These  enormous  quantities  of  gases  and  heavily  charged  brine 
cannot  be  obtained  except  from  the  interior  magma  along  deep  faults 
and  these  are  remarkably  well  indicated  all  through  that  country  by 
the  linear  directions  of  all  these  deposits  or  salt  domes. 

E.  W.  SHAW,*  Washington,  D.  C. — We  have  great  need  for  more 
detailed  information  concerning  individual  salt  domes.  If  those  who 
have  studied  them  for  years,  have  examined  hundreds  of  well  records, 
and  studied  the  outcropping  rocks  would  tell  us,  for  example,  just  what 
domes  are  known  to  have  salt,  if  all  of  these  domes  have  cap  rocks,  if 
the  cap  rock  is  ever  around  the  sides  or  on  the  slopes  of  the  dome,  as  well 
as  on  top,  and  whether  or  not  it  is  certain  that  all  that  is  called  cap  rock 
is  of  secondary  origin,  the  height  and  shape  of  each  dome  as  shown  by 
structure  and  convergence  maps,  how  much  indurated  rock  is  involved  in 
each  uplift,  the  composition  of  the  cap  rock  from  dome  to  dome;  and 
other  details,  we  might  find  the  basis  for  one  or  more  inferences  of  value. 
For  example,  if  the  cap  rock  is  due  to  diffusion  and  represents  a  chemical 
reaction  arising  out  of  the  introduction  of  salt  or  some  other  substance 
into  the  strata,  one  might  expect  the  process  to  affect  everything  around 
the  deposit  of  salt — sides  as  well  as  top. 

66  Volcanic  Origin  of  Oil.     Trans.  (1905)  35,  288. 
*  Geologist,  U.  S.  Geological  Survey. 


324        SECONDARY  INTRUSIVE  ORIGIN  OF  GULF  COASTAL  PLAIN  SALT  DOMES 

The  speaker  has  stated  that  there  is  evidence  of  sufficient  gas  in  the 
region  to  meet  the  quantity  demand  for  the  evaporation  of  enough  salt 
water  to  yield  the  enormous  quantities  of  salt  in  the  domes.  I  have  not 
had  time  to  go  over  the  figures  lately,  but  two  or  three  years  ago  I  tried 
to  estimate  about  how  much  gas  would  be  required  and  found  that  the 
amount  required  for  one  dome  was  considerably  more  than  all  of  the 
natural  gas  that  the  United  States  has  produced  to  date,  as  a  matter 
of  fact  several  hundred  thousand  times  as  much.  That  is  over  and 
above  the  problem  of  whether  the  salt  water  and  necessary  migration 
of  the  salt  water  to  the  points  of  deposit  has  been,  or  is  likely  to  have  been, 
of  such  a  nature  as  to  have  yielded  the  quantities  of  salt. 

On  page  311,  it  is  stated:  "Thus,  the  researches  of  Mills  and  Wells 
have  eliminated  the  last  barrier  to  the  acceptance  of  deposition  from 
solution  as  the  origin  of  salt  and  associated  materials."  It  seems  to  me 
that  this  statement  is  quite  erroneous  for  two  reasons.  One  is  that  when 
gas  evaporates  salt  water  and  deposits  salt,  the  salt  closes  the  pores  and 
the  process  is  self-inhibiting,  whether  it  occurs  in  the  bottom  of  a  well, 
or  in  fissures  or  other  cavities  at  great  depth  or  near  the  surface.  The 
other  is  that  enormous  quantities  of  gas  and  salt  water  are  required  at  the 
point  where  the  salt  is  being  deposited. 

JOSEPH  E.  POGUE,  New  York,  N.  Y. — A  few  years  ago  I  made  a 
hasty  examination  of  an  old  salt  mine  in  Colombia.  This  is  a  great 
mass  of  salt  near  the  surface,  and  at  the  time  I  was  impressed  with  the 
resemblance  of  this  deposit  to  the  Gulf  salt  domes  in  a  general  way. 
This  salt  deposit  was  quite  evidently  an  intrusion  in  the  surrounding 
strata,  the  evidence  of  that  conclusion  being  the  nature  of  the  contact, 
the  inclusion  of  shale  and  other  sediments  along  the  borders  of  the  salt 
mass,  and  the  general  contorted  character  of  the  salt  mass.  My  impres- 
sion at  the  time  was  that  the  salt  was  forced  into  the  surrounding  rock  in 
much  the  same  condition  as  a  plastic  mass  of  tooth  paste  extrudes  out  of 
the  container;  in  other  words,  the  material  came  in  from  a  lower  level 
under  pressure. 

F.  G.  CLAPP,  New  York,  N.  Y. — In  discussing  the  origin  of  the  salt 
domes,  we  have  made  little  effort  to  take  into  account  all  known  factors 
concerning  salt  domes,  to  say  nothing  of  the  unknown  factors.  For 
instance,  in  the  case  of  Louisiana  domes,  we  know  that  regardless  of 
whether  or  not  the  alignment  is  important  and  whether  or  not  the 
phenomena  are  deep-seated  or  superficial  the  domes  are  arranged  in  lines. 
Going  north  into  central  Arkansas,  we  find  an  intersection  of  two  lines 
of  volcanic  phenomena,  or  intrusion  of  igneous  rock,  two  of  which  rise 
several  hundred  feet  above  the  earth's  surface.  The  third  igneous 
intrusion  is  about  the  same  distance  from  the  second  that  the  second  is 


DISCUSSION  325 

from  the  first,  but  not  conspicuous,  although  fragments  of  volcanic 
rock  of  similar  character  are  found  in  the  bottoms  of  gullies  traversing 
the  region.  At  a  greater  distance  from  the  two  known  intrusives  is  the 
Arcadelphia  salt  dome  or  salt  marsh.  In  considering  the  origin  of  the 
salt  domes,  it  seems  necessary  to  consider  whether  this  feature  only  100 
mi.  or  so  north  of  Louisiana  may  have  some  bearing  on  the  Louisiana 
question. 

The  parallelism  of  salt-dome  distribution  with  the  distribution  of 
volcanic  phenomena  has  been  contradicted  in  Mexico,  though  not  so 
convincingly  but  that  some  truth  may  exist  in  this  parallelism;  and  it  is 
worth  while  to  consider  whether  there  may  not  be  some  connection 
between  the  two  classes  of  phenomena. 

It  is  a  question  whether  all  European  geologists  have  accepted  the 
theory  of  salt  having  been  pushed  in  from  underlying  and  pre-existing 
salt  beds.  I  think  the  theory  originated  in  the  German  fields  and 
possibly  with  the  German  geologists;  but  in  the  Transylvania  fields  many 
conditions  appear  discordant  with  that  hypothesis.  There  seems  to  be 
no  more  evidence  than  in  Louisiana  that  the  strata  were  underlain  by 
salt  beds. 

In  the  same  field  there  is  evidence  that  some  domes  may  still  be 
rising  and  I  have  heard  that  even  in  the  Louisiana  fields  evidence  exists 
that  some  salt  domes  may  still  be  rising.  In  Transylvania,  one  evidence 
is  the  existence  in  places  of  salt  at  the  surface — salt  not  covered  by 
superficial  deposits  but  by  vegetation,  old  trees,  etc.,  which  show  signs  of 
movement  during  the  time  of  growth  which  at  most  cannot  be  more 
than  fifty  years.  Evidence  that  the  folding  was  not  limited  to  ancient 
periods  seems  to  exist  in  the  pinching  out  of  strata  as  they  approach  the 
dome  in  some  of  the  Red  Beds  in  southwest  Oklahoma  and  in  the  Tertiary 
deposits  of  Transylvania.  We  must  consider  the  dome  problem  from 
a  worldwide  viewpoint,  rather  than  on  the  basis  of  evidence  furnished  by 
one  field  like  Louisiana. 

E.  DEGOLYEB  New  York,  N.  Y. — The  indicated  intention  of  the 
author  is  twofold:  to  disprove  the  theory  of  intrusive  origin  of  the 
gulf  coast  salt  domes  and  to  propose  a  more  acceptable  theory.  To  my 
mind  he  accomplishes  neither.  The  bulk  of  his  argument  against  the 
theory  of  intrusive  origin  concerns  itself  with  critical  discussion  of  the 
fact  that  we  know  of  no  bedded  salt  deposits  in  the  rocks  of  the  coastal 
plain  which  might  have  served  as  a  source  for  the  intrusion  of  the  salt 
core  or  stock  of  the  dome.  This  lack  of  knowledge  of  the  existence  of 
salt  deposits  of  sufficient  magnitude  has  always  constituted  a  weakness 
of  the  tectonic  theory,  as  well  recognized  and  stated  by  its  adherents  as 
by  its  opponents. 

The  simple  fact  is  that  we  do  not  know  whether  there  are  bedded 


326        SECONDARY  INTRUSIVE  ORIGIN  OF  GULF  COASTAL  PLAIN  SALT  DOMES 

deposits  of  salt  or  not.  Any  required  by  the  theory  of  intrusive  origin 
would  obviously  lie  below  the  salt  of  our  known  domes.  The  deepest 
wells  in  the  Gulf  coast  that  have  penetrated  the  domes  have  not  gone 
below  the  salt  of  the  stock.  As  an  example,  the  Producers  Oil  Co.  well 
No.  17,  Block  29,  of  the  Wheeler  &  Pickens  Fee  at  Humble,  penetrated 
the  salt  stock  of  the  Humble  Dome  at  a  depth  of  2342  ft.  and  continued 
in  it  to  5410  ft.,  where  the  well  was  abandoned  without  having  gone 
through  the  salt.  Manifestly,  according  to  the  theory  of  intrusive 
origin,  any  bedded  salt  deposit  necessary  as  a  source  of  the  salt  of  this 
stock  would  lie  below  this  depth  of  5410  ft.  and  clearly,  below  our  zone  of 
knowledge. 

It  may  be  objected  that  the  stratigraphic  horizon  equivalent  to  a  5410 
ft.  depth  at  Humble,  lies  at  much  shallower  depths  farther  northward, 
that  it  outcrops  in  fact  and  consequently  lies  well  within  our  zone  of 
knowledge.  This  must  be  admitted,  but  other  salt  domes  show  the  salt 
below  still  lower  horizons  stratigraphically.  In  the  Palestine,  Texas, 
dome,  certainly  Eagleford  and  probably  Woodbine,  the  base  of  the  Gulf 
series  of  the  Upper  Cretaceous,  has  been  recognized.  The  source  of  the 
salt  then  must  have  been  below  this  horizon  and,  consequently,  through- 
out most  of  the  coastal  plain,  entirely  below  our  zone  of  knowledge.  The 
information  yielded  by  Mr.  Matterson's  examination  of  over  1000  well 
logs  is  not  of  value  in  this  investigation  because  it  is  not  from  the  horizons 
in  which  we  are  interested. 

It  seems  quite  probable,  if  the  intrusive  theory  is  correct,  that  the 
salt  domes,  as  we  at  present  know  them,  had  their  origin  in  folded  and 
faulted  pre-Cretaceous  rocks  upon  which  our  Cretaceous  and  more  recent 
rocks  lie  unconformably  as  a  masking  mantle  and  that  the  salt  stocks 
themselves  were  forced  upward  into  this  more  recent  mantle.  This  is 
pure  speculation,  but  so  is  every  other  theory  of  salt-dome  origin  that  has 
come  to  my  attention. 

The  tectonic  theory  is  not  more  deficient  in  its  failure  to  account  for 
a  source  of  the  salt  than  is  any  of  the  various  theories  of  deposition  from 
solution.  Simple  explanations  of  deposition  from  natural  brines,  particu- 
larly connate  waters,  whether  with  the  assistance  of  gas  evaporation, 
as  suggested  by  Mills  and  Wells,  is  not  enough.  There  are  many  places 
in  the  world  where  faults,  even  cross  faults,  are  common  and  where  brine 
and  natural  gas  are  also  as  common  as  on  the  Gulf  Coast,  yet  where  salt 
domes  do  not  exist. 

Many  of  Mr.  Matteson's  other  arguments  are  quite  faulty.  His 
attempt  to  discredit  the  apparent  analogy  between  American  and  Euro- 
pean domes  will  not  hold.  The  resemblances  between  the  two  types  is 
much  more  marked  than  is  their  differences  and  in  the  Isthmus  of  Tehuan- 
tepec  region  of  Mexico,  the  differences  are  still  further  sunk  since  good 
examples  of  both  types  are  present  in  the  same  area. 


DISCUSSION  327 

It  is  not  true  in  the  American  domes  that  "  areas  and  blocks  of  older, 
underlying  formations  have  not  been  upthrust  so  as  to  be  exposed  at  or  to 
lie  near  the  surface"  as  is  the  case  with  certain  European  domes.  The 
Cretaceous  is  thrust  up  through  the  Tertiary  in  many  of  the  north  Louis- 
iana and  Texas  domes.  The  Palestine  dome  shows  such  an  upthrust  of 
the  order  of  3500-4000  ft.  beyond  any  question.  At  Tonolapa,  on  the 
Cececapa  dome,  in  the  Isthmus  of  Tehuantepec,  Jurassic  limestones  have 
been  thrust  upward  several  thousand  feet,  coming  to  the  surface  through 
Miocene  or  Miocene-Pliocene  marls. 

Nor  is  Mr.  Matteson  more  fortunate  in  his  conclusion  that  the  salt 
of  American  salt  domes  cannot  be  free  from  bedded  deposits  because 
"  potassium  salts,  such  as  are  commonly  associated  with  bedded  deposits 
of  rock  salt,  are  practically  missing. "  Phelan57  gives  analyses  of  salt, 
brines,  and  bitterns  from  various  bedded  deposits  and  domes  in  the 
United  States.  The  chemical  composition  of  the  various  salts  is  re- 
markably uniform  and  there  is  no  variation  between  salt-dome  salt  and 
bedded  salt  deposits  greater  than  the  variation  between  various  sam- 
ples from  bedded  deposits.  The  same  is  true  with  regard  to  natural 
brines  except  that  brines  from  Humble  and  Sour  Lake,  both  salt  domes, 
show  slightly  higher  potassium  contents  than  other  brines — the  direct 
opposite  of  Mr.  Matteson's  argument. 

The  theory  that  Mr.  Matteson  proposes  as  a  substitute  is  one  that 
includes  bits  from  all  previously  proposed  theories.  This  is  its  strength 
as  well  as  weakness,  since  many  forces  have  probably  combined  to  pro- 
duce a  salt  dome.  We  are  interested,  however,  principally  in  the  main 
force  forming  the  salt  dome.  We  might  consider  a  dome  as  a  structural 
feature  alone.  Of  course,  the  salt  is  common  to  all  of  them,  but  there 
are  domes  that  have  no  cap  rocks,  sulfur,  or  oil.  What  theory  will 
explain  the  tremendous  upthrust  by  which  blocks  of  sediments  %  or  1  mi. 
in  diameter  are  thrust  upward  4000  ft.  to  perhaps  much  greater  distances, 
through  rocks  of  younger  age?  I  do  not  believe  that  Mr.  Matteson's 
theory  will  meet  this  test  nor  do  I  believe  that  any  other  theory  of  deposi- 
tion from  solution  is  sufficient. 

Of  course,  much  can  be  said  for  every  theory.  I  do  not  believe,  for 
example,  that  the  volcanic  theory  is  acceptable,  but  it  explains  fairly 
well  some  facts  difficult  to  explain  by  any  other  theory.  It  explains 
the  hot  waters  associated  with  the  domes  and  it  is  more  satisfactory  in 
explaining  the  extremely  high  sulfur  oils  of  coastal  Texas  and  Louisiana, 
the  Tampico  region,  and  the  Isthmus  of  Tehuantepec  region,  two  salt 
dome  regions  and  one  region  of  volcanic  activity,  than  is  any  other  theory. 

W.  G.  MATTESON. — As  to  the  impossibility  of  admitting  that  such 
great  quantities  of  salt  could  be  leached  from  the  various  sediments  under- 

w  U.  S.  Geol.  Survey  Bull.  669. 


328        SECONDARY  INTRUSIVE  ORIGIN  OF  GULF  COASTAL  PLAIN  SALT  DOMES 

lying  the  coastal  plain  area,  the  researches  of  Mr.  Kennedy  have  proved 
conclusively  that  just  in  the  Miocene  deposits  alone  there  is  enough  dis- 
seminated salt  content  to  account  for  the  salt  in  these  coastal  domes. 
Besides,  there  are  the  underlying  formations  with  disseminated  salt  in  the 
Cretaceous  deposits,  which  we  know  may  be  considerable. 

Mr.  Shaw  questioned  the  advisability  of  having  more  detailed  infor- 
mation on  the  cap  rock.  The  major  operating  companies  in  the  Gulf 
coastal  plain  area  recognize  the  importance  of  geological  application, 
especially  since  the  bringing  in  of  oil  around  some  of  the  older  formerly 
abandoned  domes.  Some  companies  have  accumulated  a  great  mass  of 
valuable  detailed  evidence.  It  is  difficult  for  a  consulting  geologist  to 
get  this  information  in  every  instance  but  this  would  be  a  good  oppor- 
tunity for  the  United  States  Geological  Survey  to  bring  up  to  date  its 
data  on  the  Gulf  coastal  plain  area.  It  is  quite  possible  that  several 
companies  would  turn  over  a  considerable  portion  of  this  information  to 
the  Survey.  The  author  has  had  access  to  some  of  this  information. 

Mr.  Shaw  raises  the  question  of  gas  being  present  in  sufficient  quantity 
to  cause  deposition  through  evaporation.  The  Yegua  formation  has 
yielded  enormous  quantities  of  gas,  and  in  many  cases  where  we  drilled 
into  that  formation  all  we  obtained  was  gas.  The  fact  that  gas  has 
been  found  from  the  Mexican  border  across  the  entire  states  of  Texas 
and  Louisiana  shows  that  the  amount  of  gas  in  this  one  formation  alone  is 
great;  in  addition  there  is  the  gas  in  the  Cretaceous  and  underlying  Penn- 
sylvanian  formations.  There  is  an  adequate  supply  of  gas  to  account  for 
great  evaporative  effects  on  salt  brines  with  the  subsequent  deposition 
of  vast  salt  masses. 

In  the  preparation  of  this  paper  I  was  able  to  consult  with  Mr. 
Kennedy,  who  has  recently  investigated  the  logs  of  wells  of  the  Freeport 
Sulfur  Co.,  at  Bryan  Heights  and  some  of  the  material  presented  herein 
was  the  result  of  that  conference. 

Mr.  DeGolyer  speaks  of  the  tremendous  upthrust  of  strata  at  the 
loci  of  domes.  First,  the  changing  of  the  limestone  into  gypsum  results 
in  an  increase  in  volume  of  from  32  to  50  per  cent.  As  we  find  a  gypsum 
cap  anywhere  from  200  to  700  ft.  in  extent,  and  probably  considerable 
of  the  gypsum  cap  has  been  eroded,  this  alteration  alone  indicates  an 
initial  uplift  of  a  few  hundred  feet. 

In  presenting  this  paper  I  admit  that  a  considerable  part  of  the  uplift 
has  been  due  to  intrusion  en  masse,  but  that  intrusion  has  occurred  after 
the  salt  has  been  deposited  relatively  near  the  surface  along  with  the 
limestone  and  other  materials.  The  upthrust  of  those  domes,  amounting 
to  close  to  4000  ft.  in  the  interior  domes,  to  which  Mr.  DeGolyer  calls 
attention,  seems  to  be  greater  than  the  average  of  1500  to  3000  ft.  which 
we  find  along  the  Gulf  coastal  plain  proper,  but  might  not  that  be  due 
to  the  fact  that  the  interior  domes  are  nearer  the  great  Bal cones  fault? 


DISCUSSION  329 

H.  W.  HIXON,  New  York,  N.  Y. — There  was  great  pressure  of  gas 
below  the  cap.  Where  gas  could  not  escape  water  certainly  could  not, 
which  shows  that  the  seal  was  complete.  Therefore,  I  do  not  believe  it 
would  be  possible  for  much  water  to  have  escaped  from  these  domes  with- 
out leaving  evidence  of  its  having  been  present. 

My  theory  of  the  origin  of  these  domes  involves  a  fundamental 
conception  of  the  physical  condition  of  matter  in  the  interior  of  the  earth. 
The  temperature  at  a  moderate  depth,  say  150  mi.,  will  be  a  critical 
temperature  for  all  the  matter  in  the  interior  of  the  earth;  after  it  passes 
the  critical  temperature  it  is-  in  a  gaseous  condition,  and  when  matter 
is  above  its  critical  temperature,  it  is  capable  of  high  compression.  Gravi- 
tational compression  unrestrained  is  capable  of  producing,  in  a  gaseous 
core,  matter  that  is  denser  than  the  solids  that  will  form  out  of  them. 
Admitting,  for  the  sake  of  argument,  that  the  gaseous  core  can  be  denser 
than  the  solids  that  will  form  out  of  it,  we  have  a  solid  crust  floating 
on  the  gaseous  core,  like  ice  floats  on  water.  Likewise,  when  matter 
changes  from  the  condition  of  gas  denser  than  solids,  to  that  of  a  solid, 
it  expands.  If  the  gaseous  core  is  expanded  by  loss  of  temperature,  the 
cold  crust  above  will  be  fractured,  and  great  fault  planes,  which  are 
called  erogenic  in  nature,  should  be  formed  and  more  or  less  parallel. 

These  fault  planes  may  be  of  two  series,  which  intersect  at  approxi- 
mately right  angles.  These  salt  domes  occur  at  the  intersections  of  those 
faults,  which  furnished  a  passage  for  volatile  material  from  the  interior. 
Whatever  shale  beds  covered  those  fault  planes  did  not  rupture  clear 
through  to  the  surface,  but  stretched  under  pressure  of  the  load  and 
completed  the  seal.  The  volatile  material  in  these  domes  rather  confirms 
that.  Salt  is  volatile  at  a  moderate  temperature,  so  is  sulfur,  and  these 
gases  come  up  in  a  dry  condition.  I  do  not  believe  there  is  any  water  to 
speak  of  in  connection  with  them,  except  that  necessary  to  alter  the  lime- 
stone cap  into  gypsum.  But  these  fault  planes,  created  by  the  expanding 
force,  have  been  the  determining  cause  of  the  domes,  and  the  gradual 
increase  of  the  size  of  the  plug  of  the  salt  domes  is  due  to  the  cumulative 
effect  of  volatile  matter  coming  up  through  the  cracks. 

R.  VAN  A.  MILLS,*  Washington,  D.  C.  (written  discussionf). — Mr. 
Matteson  not  only  contributes  new  and  valuable  data,  resulting  from 
his  investigations,  but  he  attacks  the  problem  on  the  basis  of  a  multiple 
hypothesis.  By  recognizing  the  grain  as  well  as  the  chaff  in  several  hypo- 
theses and  by  applying  such  parts  of  these  hypotheses  as  accord  with  the 
facts  thus  far  established,  he  has  adopted  the  most  promising  method  of 
attacking  the  salt  dome  problem.58 

*  Petroleum  Technologist,  Bureau  of  Mines. 

t  By  permission  of  Director  of  Bureau  of  Mines. 

68  R.  Van  A.  Mills:  Discussion  on  Oil-field  Brines.    See  page  281. 


330     SECONDARY  INTRUSIVE  ORIGIN  OF  GULF  COASTAL  PLAIN  SALT  DOMES 

That  we  are  in  no  position  to  restrict  ourselves  to  any  one  of  the 
theories  previously  advanced  is  recognized  from  several  facts.  The 
presence  of  deep-seated  salt  beds  in  the  Gulf  coastal  region  from  which 
intrusive  masses  of  salt  might  originate  has  never  been  established;  the 
evidence  presented  by  Mr.  Matteson,  so  far  as  it  goes,  is  rather  against 
the  presence  of  such  beds.  Again,  there  has  been  no  systematic  geo- 
chemical  study  of  the  domal  materials  or  associated  waters,  gases,  and 
oils,  to  determine  their  relationships  together  with  the  geochemical  proc- 
esses that  have  probably  been  operative  in  the  dome  building.  Strange 
to  say,  the  only  published  results  of  a  systematic  investigation  of  this 
kind  come  from  the  Appalachian  region59  where  there  are  no  salt 
domes. 

We  agree  that  there  has  been  intrusion  by  salt  but  we  know  neither 
the  origin  of  the  salt  nor  the  causes  for  the  intrusion.  Our  theories 
upon  these  phenomena  constitute  little  more  than  working  hypotheses 
through  which  to  attack  the  problem.  Accepting  this  view,  real  progress 
must  come  through  systematic  and  laborious  investigation  rather  than 
by  the  easy  and  alluring  road  of  speculation. 

Advocates  of  the  theory  of  primary  intrusion  of  the  salt  masses  have 
endeavored  to  substantiate  that  idea  by  inadequate  data  and  also  by  elimi- 
nating all  theories  upon  the  deposition  of  salt  from  solution.  They  have 
also  attributed  undue  importance  to  the  so-called  flowage  lines  in  the 
salt  masses;  first,  because  the  lines  may  be  caused  by  secondary  intrusion, 
and  second,  because  the  lines  may  be  of  depositional  origin.  Such  lines 
commonly  appear  in  specimens  of  the  mineral  salts  deposited  through 
the  agency  of  water  in  oil  and  gas  wells.  The  lines  are  especially  com- 
mon in  deposits  of  sodium  chloride.  Laboratory  experiments  indicate 
that  lines  of  this  kind  in  masses  of  salt  deposited  from  solution  may  be 
largely,  or  wholly,  of  depositional  origin.  Irregular  bands  or  lines  in 
the  salt  and  gypsum  deposits  of  southwestern  Virginia  are  attributed 
to  secondary  depositional  phenomena  by  Stose.60  Conditions  in  that  lo- 
cality apparently  preclude  any  probability  that  the  masses  of  salt  and 
gypsum  attained  their  present  positions  and  irregularly  banded  char- 
acteristics through  intrusion. 

To  what  extent  the  growth  of  crystals  may  have  contributed  toward 
the  intrusion  of  the  salt  and  uplifting  of  superencumbent  strata  in  the 
Gulf  coastal  region  is  problematic.  It  is  recognized  that  enormous 
forces  are  exerted  in  the  growth  of  concretions  and  that  certain  failures 
of  concrete  are  caused  by  the  forces  of  crystallization,  but  data  upon  the 


*9  R.  Van  A.  Mills  and  Roger  C.  Wells:  Evaporation  and  Concentration  of  Waters 
Associated  with  Petroleum  and  Natural  Gas.  U.  S.  Geol.  Survey  Bull.  693  (1919). 

60  George  W.  Stose:  Geology  of  the  Salt  and  Gypsum  Deposits  of  Southwestern 
Virginia.  Virginia  Geol.  Survey  Bull.  7  (1913),  70-71. 


DISCUSSION  331 

forces  exerted  through  the  crystallization  of  salt  are  meager.  Rogers61 
cited  data  indicating  that  such  forces  would  be  inadequate  to  cause  the 
intrusion  of  the  salt  with  the  consequent  uplifting  of  superencumbent 
beds.  He  did  not  however,  show  that  such  forces  were  inoperative. 
They  have  undoubtedly  played  their  part.  In  laboratory  experiments 
upon  the  cementation  of  sands  and  the  exclusion  of  water  from  oil  wells 
by  plugging  the  interstices  of  the  sands  through  chemical  precipitation, 
numerous  instances  of  the  displacement  of  sand  by  crystalline  growths 
have  been  observed.  The  crystaline  precipitates  formed  masses  that 
displaced  the  loose  sands.  In  these  experiments,  repeated  failures  of 
the  glass  fronts  of  the  apparatus  were  caused  by  the  expansive  effects 
of  the  crystallization  of  chlorides,  sulfates,  carbonates,  and  silicates. 

Recognizing  that  in  the  light  of  the  meager  information  now  available, 
the  effects  attributed  to  the  forces  of  growing  crystals  by  Harris62  con- 
stitute a  weakness  in  his  theory,  but  also  recognizing  that  the  intrusion 
of  salt  from  one  cause  or  another  has  played  a  major  role  in  the  dome 
building,  it  is  logical  for  Mr.  Matteson  to  postulate  intrusion  through  the 
agency  of  dynamic  forces  acting  from  without  the  salt  cores  themselves. 
The  hypothesis  of  secondary  intrusion,  together  with  that  of  geochemical 
origin  of  the  cap  rocks,  constitute  valuable  working  hypotheses  for  future 
investigations. 

Where  so  much  has  to  be  taken  for  granted  and  so  much  more  has 
yet  to  be  learned  through  deep  drilling,  accompanied  by  systematic  in- 
vestigation, it  is  not  to  be  assumed  that  Mr.  Matteson  has  presented  the 
ultimate  explanation  for  the  origin  of  the  Gulf  coastal  domes.  We 
must,  however,  recognize  that  his  method  of  attacking  the  problem  is 
an  important  step  toward  the  ultimate  solution. 

W.  G.  MATTESON  (author's  reply  to  discussion). — The  director  of  the 
U.  S.  Geological  Survey  recently  assigned  M.  I.  Goldman  to  the  Gulf 
Coast  province  for  the  purpose  of  making  a  thorough  study  of  the  pres- 
ence, variation  in  composition,  physical  character,  and  so  forth  of  the 
cap  rock  of  the  coastal  plain  salt  domes. 

Mr.  E.  W.  Shaw  says  that  "we  have  great  need  for  more  detailed 
investigation  concerning  individual  salt  domes;"  yet  much  of  the  specified 
information  he  desires  has  been  obtained.  Unfortunately,  however,  such 
data  have  not  been  gathered  within  one  cover,  for  this  would  require  a 
monograph  that  only  special  organizations  like  the  Survey  have  the 
facilities  to  produce.  As  Messrs.  Shaw  and  Mills  state,  an  extensive 
geochemical  investigation  of  the  coastal  plain  domes  is  needed,  yet  such 

61  G.  Sherburne  Rogers:  Intrusive  Origin  of  Gulf  Coast  Salt  Domes.  Econ.  Geol. 
(1918)  13,  447-485. 

"Gilbert  D.  Harris:  Rock  Salt  in  Louisiana.  Louisiana  Geol.  Survey  Bull  7 
(1907). 


332   SECONDARY  INTRUSIVE  ORIGIN  OF  GULF  COASTAL  PLAIN  SALT  DOMES 

an  investigation  is  not  without  its  difficulties.  To  be  of  greatest  value, 
it  should  be  as  extensive  as  outlined  by  Mr.  Shaw,  but  this  would  require 
several  years  of  field  work,  considerable  expense,  and  probably  constant 
change  in  the  personnel  of  the  investigators.  Indeed,  it  is  doubtful  if 
some  of  the  information  can  be  obtained.  An  examination,  last  3rear,  of 
a  proved  dome  required  several  months  of  persistent  effort.  The  dome 
had  never  produced,  yet  twenty  wells  had  demonstrated  its  character 
and  some  of  these  wells  had  excellent  oil  showings.  In  preparing  the 
map,  it  was  necessary  to  find  the  drillers  and  then  have  them  locate,  in 
the  dense  underbrush,  the  abandoned  wells.  Six  months  were  required 
to  secure,  from  varied  scattered  sources,  the  logs  of  these  twenty  wells. 
Some  of  the  large  companies  that  had  drilled  on  the  dome  had  no  logs,  so 
that  information  could  be  obtained  only  by  finding  some  outside  person 
who  was  interested  in  the  tests  at  the  time.  If  only  the  present  producing 
domes  were  thoroughly  investigated  geochemically,  much  new  and  valu- 
able information  would  certainly  be  procured.  In  this  connection,  it  is 
to  be  earnestly  hoped  that  the  U.  S.  Geological  Survey  will  increase  the 
scope  of  its  present  activity  in  the  Gulf  Coast  region  by  having  Messrs. 
Mills  and  Wells  continue  their  researches,  which  have  been  so  fruitful 
in  the  Appalachian  province. 

It  is  unfortunate  that  Mr.  Shaw  did  not  accompany  his  statements 
respecting  the  quantity  of  gas  necessary  to  cause  vast  salt  deposition 
through  evaporation  with  adequate  data  and  an  outline  of  the  method 
by  which  he  arrived  at  such  conclusions,  as  his  assertion  is  debatable. 
Records  show  that  the  Yagua  formation,  of  Eocene  age,  has  yielded  many 
billions  cubic  feet  of  gas  in  the  Gulf  Coast  region  and  has  an  estimated 
possible  potential  production  even  more  vast.  Yet  this  is  only  one  for- 
mation of  several  that  are  gas  bearing.  Mills  and  Wells63  call  specific 
attention  to  the  fact  that  relatively  small  quantities  of  gas  were  capable 
of  causing  deposition  of  several  tons  of  salt  in  24  hr.  hi  certain  wells  in  the 
Appalachian  province.  The  statement  that  "  when  gas  evaporates  salt 
water  and  deposits  salt,  the  salt  closes  the  pores  and  the  process  is  self- 
inhibiting,"  is  merely  speculation  on  Mr.  Shaw's  part.  The  only  pub- 
lished data  relating  to  this  phase  are  those  of  Mills  and  Wells64,  and 
apparently  they  find  nothing  to  warrant  the  conclusions  of  Mr.  Shaw. 

The  author  was  much  surprised  that  Mr.  DeGolyer  should  select  the 
Palestine  salt  dome  in  Anderson  County,  Texas,  as  an  example  of  up- 
thrust  similar  to  that  observed  in  European  occurrences  and,  on  this 
basis,  question  the  reliability  of  the  writer's  conclusions.  The  writer 
made  a  thorough  investigation,  a  few  years  ago,  of  the  Palestine  dome  and 


•»R.  Van  A.  Mills  and  R.  C.  Wells:  Evaporation  and  Concentration  of  Waters 
Associated  with  Petroleum  and  Natural  Gas.    U.  S.  Geol.  Survey  Bull.  693. 
64  W.  G.  Matteson:  Op.  cit.,  3. 


DISCUSSION  333 

the  Keechi  dome,  several  miles  to  the  northeast.  The  Austin  Chalk  and 
overlying  formations  of  Upper  Cretaceous  age  are  here  found  at  the  sur- 
face entirely  surrounded  by  the  Wilcox  formation,  of  Lower  Eocene  age. 
There  is  no  question  that  faulting  has  occurred,  yet  the  evidence  shows 
the  Wilcox  to  be  tilted  at  angles  of  30°  to  40°  and  sloping  from  the  center 
of  the  dome  on  all  sides.  Likewise,the  Wilcox  is  the  next  younger  over- 
lying formation  of  the  geologic  series  in  this  specific  area,  the  Midway 
being  absent.  In  few  instances  is  the  evidence  of  uplift  (and  not  up- 
thrust)  accompanied  by  faulting  and  followed  by  erosion  more  positive 
than  here,  this  erosion  revealing  the  presence  of  the  immediately  under- 
lying Cretaceous  formations.  Few  experienced  Gulf  Coast  investigators 
will  agree  with  Mr.  DeGolyer  that  these  occurrences  in  Texas  and  North 
Louisiana  are  real  upthrusts  of  older  formations  into  younger  and  es- 
pecially of  the  nature  and  extent  to  justify  their  classification  with  the 
European  occurrences,  where  formations  have  been  completely  sheared 
from  their  parent  beds  and  upthrust  many  thousands  of  feet  into  much 
younger  horizons,  which  horizons  in  no  way  show  the  deformations 
characteristic  of  the  older  rocks.  While  the  presence  of  the  Austin  Chalk 
at  the  surface  at  the  Palestine  and  Keechi  domes  seemed  to  indicate  a 
local  uplift  of  3000  to  4000  ft.,  with  the  information  available  at  that  time, 
recent  data  point  to  the  Sabine  uplift  being  much  more  extensive  than 
commonly  supposed  while  the  influence  of  the  Balcones  fault  must  also 
be  considered.  It  is  quite  probable,  therefore,  that  the  Cretaceous 
formations  here  are  not  so  deep  lying  as  supposed  and  that  the  amount  of 
uplift  will  necessarily  have  to  be  modified. 

The  negative  character  of  the  results  obtained  by  Phelan  in  his 
analyses  of  bedded  salt  and  salt-dome  deposits  and  brines  does  not  justify 
any  positive  conclusions  tending  to  disprove  the  writer 's  statements. 
While  potassium  salts  may  not  have  been  characteristic  of  the  bedded 
deposits  analyzed  by  Phelan,  it  is  generally  agreed  that  extensive  bedded 
deposits  are  often  so  characterized  by  such  salts  along  with  anhydrite. 
Van  der  Gracht65  and  Kennedy66  have  admitted  the  difficulty  of  assigning 
an  exactly  similar  mode  of  origin  to  both  the  European  and  the  American 
salt  domes,  due  to  the  general  absence  of  potassium  salts  in  the  latter 
instance,  and  the  opinion  of  these  authorities  cannot  be  lightly  disre- 
garded. The  potassium  content  of  Humble  and  Sour  Lake,  mentioned 
by  DeGolyer,  is  very  slight  and  might  be  due  to  several  factors.  Such 
occurrences  are  of  little  value  in  the  present  discussion. 

The  writer  finds  no  basis  to  justify  Mr.  DeGolyer 's  conclusion  that  the 
1000  logs  examined  in  the  present  instance  are  of  no  value  since  they 

66  W.  A.  I.  M.  von  Waterschoot  van  der  Gracht:  Salt  Domes  of  Northwestern 
Europe.    Southwestern  Assn.  Pet.  Geol.,  Bull  1  (1917). 
66  Personal  interview. 


334   SECONDARY  INTRUSIVE  ORIGIN  OF  GULF  COASTAL  PLAIN  SALT  DOMES 

represent  wells  that  have  not  penetrated  below  Tertiary  horizons.  These 
logs,  selected  with  extraordinary  care,  include  a  series  of  wells  penetrating 
varying  formations  from  the  lower  Pennsylvanian  to  the  Recent,  yet 
in  not  a  single  instance  has  the  presence  of  bedded  salt  deposits  been 
detected  in  the  Pennsylvanian,  Cretaceous,  or  Tertiary.  DeGolyer 
says  "the  deepest  wells  in  the  Gulf  Coast  that  have  penetrated  the  domes 
have  not  gone  below  the  salt  of  the  stock"  but  Kennedy67  records  a  well 
that  passed  completely  through  the  salt  into  the  underlying  formations. 
DeGolyer  asks,  "what  theory  will  explain  the  tremendous  upthrust  by 
which  blocks  of  sediments,  %  to  1  mi.  in  diameter,  are  thrust  upwards 
4000  ft.  to  perhaps  greater  distances?"  This  question  of  uplift  and  not 
upthrust  is  logically  explained  on  pages  317  to  319  and  the  explanation 
herein  offered  accords  strictly  with  all  facts.  It  is  quite  evident,  however, 
that  the  primary  intrusive  origin  that  Mr.  DeGolyer  is  attempting  to 
substantiate  will  in  no  way  adequately  answer  his  question,  for  there  is 
absolutely  no  evidence  of  the  action  of  orogenic  forces  of  sufficient  in- 
tensity in  the  Gulf  Coast  region  to  push  salt  masses  and  accompanying 
sediments  upwards  through  thousands  of  feet  of  overly  ing  materials. 
Moreover,  why  should  we  not  find  Cretaceous  and  older  formations 
overlying  the  salt  in  the  domes  along  the  Gulf  Coast  proper,  or  at  least 
fragmentary  evidence  of  the  same,  if  there  is  any  merit  in  Mr.  DeGolyer 's 
contention  that  "if  the  primary  intrusive  theory  is  correct,  the  salt  domes 
had  their  origin  in  folded  and  faulted  pre-Cretaceous  rocks  upon  which 
our  Cretaceous  and  more  recent  rocks  lie  unconformably  as  a  masking 
mantle  and  that  the  salt  stocks  themselves  were  forced  upwards  into  this 
more  recent  mantle?" 

In  concluding  the  discussion,  it  might  not  be  remiss  to  utter  a  word 
of  caution  against  the  tendency  to  speculate  without  sufficient  basis  of 
fact.  The  Gulf  Coast  salt  domes  offer  a  most  alluring  field  in  this  respect 
and  the  temptation  has  been  too  great  for  some  of  our  most  able  authori- 
ties to  resist.  After  all,  a  theory  is  only  a  suitable  working  hypothesis 
conforming  to  reason  and  observed  conditions.  As  Mr.  Mills  says  about 
the  problems  of  these  domes,  "  real  progress  must  come  through  system- 
atic and  laborious  investigation  rather  than  by  the  easy  and  alluring  road 
of  speculation." 


67  William  Kennedy:  Coastal  Salt  Domes.     Southwestern  Assn.  Pet.  Geol.,  Bull. 
1,  and  personal  interview. 


APPLICATION   OF  LAW   OF   EQUAL   EXPECTATIONS  335 


Application  of  Law  of  Equal  Expectations  to  Oil  Production 

in  California* 

BY  CARL  H.  BEALJ  AND  E.  D.  NOLAN,  t  WASHINGTON,  D.  C. 


(Chicago  Meeting,  September,  1919) 


IN  February,  1918,  the  conclusion  was  published  by  Lewis  and  Beal 
"that  wells  of  equal  output  on  the  average  will  produce  equal  amounts 
of  oil  in  the  future,  regardless  of  the  ages  of  the  wells."  This  conclusion 
was  based  upon  the  study  of  data  collected  principally  in  Oklahoma  and 
was  not  known  at  that  time  to  be  true  for  other  oil  fields.  An  abundance 
of  statistical  proof  was  later  collected  by  the  senior  author  of  the  present 
paper,  which  showed  that  the  conclusion  was  undoubtedly  well  founded 
and  that  it  applied  to  other  fields  as  well.  Accordingly,  it  was  later 
restated2  as  the  "law  of  equal  expectations"  as  follows:  "If  two  wells 
under  similar  conditions  produce  equal  amounts  during  any  given  year, 
the  amounts  they  will  produce  thereafter,  on  the  average,  will  be  approxi- 
mately equal,  regardless  of  their  relative  ages." 

Although  only  scanty  data  from  the  California  oil  fields  were  avail- 
able at  the  time  this  publication  was  prepared,  sufficient  information  was 
analyzed  upon  which  to  base  the  insert  on  Fig.  80,  which  showed  beyond 
a  doubt  that  the  law  held  at  least  for  a  part  of  the  Midway  oil  field  in 
California.  Recently  the  authors  have  collected  more  complete  data 
in  California,  and  it  is  the  purpose  of  this  paper  to  explain  the  method 
used  in  demonstrating  the  truth  of  the  law  and,  in  addition,  to  give 
several  methods  by  which  curves  constructed  in  accordance  with  this 
law  can  be  used  in  a  practical  way  with  ease  and  accuracy. 

THE  FAMILY  CUKVE 

The  law  of  equal  expectations  means  that  each  individual  of  a  group  of 
wells  producing  under  similar  conditions  will  decline  along  approximately 
the  same  type  of  curve,  the  rapidity  of  decline  varying  with  the  output 


*  Published  by  permission  of  the  Director,  U.  S.  Bureau  of  Mines. 

t  Petroleum  Technologist,  U.  S.  Bureau  of  Mines. 

$  Consulting  Petroleum  Engineer,  U.  S.  Bureau  of  Mines. 

1  Some  New  Methods  of  Estimating  the  Future  Production  of  Oil  Wells.     Trans. 
(1918)  59,  492. 

2  Carl  H.  Beal:  The  Decline  and  Ultimate  Production  of  Oil  Wells  with  Notes  on 
the  Valuation  of  Oil  Properties.     U.  S.  Bureau  of  Mines  Bull.  177  (1919)  36. 


336  APPLICATION   OP  LAW   OF  EQUAL   EXPECTATIONS 

of  the  well.  For  instance,  if  the  first  year's  production  of  a  well  is  very 
large,  its  decline  will  be  much  more  rapid  than  that  of  a  well  having  a 
smaller  output.  Furthermore,  the  second  well  will  produce  oil  at  the 
same  rate  as  the  first  well  after  the  latter  has  declined  to  the  same  out- 
put as  the  second.  Inasmuch  as  the  wells  in  a  group,  under  similar  con- 
ditions, produce  oil  along  a  certain  curve,  if  this  curve  can  be  made  up 
from  decline  records  of  wells  of  different  size,  we  are  able  to  forecast  with 
accuracy  the  decline  of  normal  wells  of  different  size  in  that  area.  Such 
curves  have  been  built  up  for  different  fields  in  California.  They  have 
been  called  "family"  curves  for  lack  of  a  better  name  and  because  the 
decline  of  wells  of  different  output  will  follow  the  same  curve. 

The  use  of  the  family  curve  is  not  claimed  to  be  original  in  the  present 
paper,  as  its  possibilities  were  given  by  Lewis  and  Beal,3  and  one  method 
of  preparing  such  a  curve  and  its  advantages  were  later  briefly  given  by 
Beal.4  The  particular  method  of  building  up  the  family  curve,  however, 
is  unique,  and  the  various  methods  of  using  the  curve  for  estimating  the 
life  and  future  production  of  wells  are  new. 


CONSTBUCTION  OF  FAMILY  CuBVE 

In  preparing  family  curves  for  other  oil  fields,  it  has  usually  been 
necessary  to  use  the  production  records  of  tracts,  for  in  most  fields  the 
output  of  all  wells  on  a  tract  is  gaged  in  the  same  tank.  The  use  of  such 
records  has  some  advantages  and  some  disadvantages.  If  the  records 
of  individual  wells  are  used,  there  will  be  smaller  chance  of  the  entrance 
of  such  complex  factors  as  the  undue  maintenance  of  production  by  the 
bringing  in  of  new  wells  on  a  tract.  In  the  oil  fields  of  California  the 
production  records  of  individual  wells  are  usually  available,  and  the  fol- 
lowing curves  are  based  entirely  on  such  records. 

Fig.  1  shows  a  family  curve  based  on  the  production  records  of  wells 
in  a  California  oil  field.  Briefly,  the  preparation  of  such  a  curve  con- 
sists of,  first,  choosing  the  records  of  all  normal  wells — such  as  those 
unaffected  by  redrilling,  cleaning  out,  deepening,  water  encroachment, 
etc.;  second,  plotting  the  yearly  decline  of  the  largest  well  A  and  joining 
the  points  showing  the  production  per  year  by  straight  lines;  and,  finally, 
taking  successively  smaller  wells  and  plotting  the  decline  of  each  well, 
the  initial  or  first  year's  point  being  located  on  the  production  curve  of  the 
largest  well  at  the  proper  point,  and  subsequent  points  at  spaces  to  the 
right  representing  years.  For  instance,  in  Fig.  1,  the  points  marked  A 
represent  the  decline  of  the  largest  well,  those  marked  B  represent  the 

»  Trans.  (1918)  69,  512,  Fig.  9. 

«  U.  S.  Bureau  of  Mines  Bull.  177  (1919)  198. 


CARL  H.   BEAL  AND   E.   D.   NOLAN 


337 


decline  of  the  second  largest  well,  and  points  C,  D,  E,  F,  G,  and  H  the 
declines  of  the  smaller  wells.  The  initial  point,  or  the  first  year's 
production,  of  well  B  is  located  on  the  curve  of  well  A  at  a  distance  of 
90,000  bbl.  (the  first  year's  production)  above  the  horizontal  axis.  This 
procedure  is  repeated  for  the  smaller  wells. 

After  the  declines  of  two  or  three  wells  have  been  plotted  the  average 
line  can  be  drawn  by  determining  the  numerical  average  of  points  within 
adjoining  vertical  segments  of  the  cross-section  paper  and  drawing  the 
curve  through  the  average  points.  From  this  time  on,  the  decline  of  the 
smaller  walls  may  be  begun  on  the  average  curve.  For  instance,  in  Fig. 
1,  after  the  records  of  wells  A  and  B  were  plotted,  the  heavy  average  line 
was  drawn  to  point  X  and  the  first  year's  production  of  wells  C,  D,  and  E 


10 


11 


23456789 
Time  Interval,  One  Space  =  One  Year 
(  Regardless  of  Starting  Point ) 

FIG.  1. — SHOWING  METHOD  USED  IN  CONSTRUCTING  A  FAMILY  CURVE  FROM  PRODUCTION 

RECORDS  OF  INDIVIDUAL  FIELDS. 

were  plotted  on  the  curve.  The  process  of  gradually  extending  the  family 
curve  and  plotting  on  it  the  initial  year's  production  of  smaller  wells  is 
continued  until  all  the  data  are  plotted.  Rarely  will  a  case  be  found  where 
the  plotting  of  more  than  three  or  four  wells  is  necessary  to  determine 
the  beginning  of  the  average  curve.  The  greatest  difficulty  is  usually 
experienced  in  determining  the  proper  rate  of  curvature  of  the  decline 
curve  when  it  begins  to  flatten  out.  This  part  of  the  curve  usually 
represents  the  exhaustion  of  the  high  gas  pressure,  which  is  closely  as- 
sociated with  the  rate  of  expulsion  of  oil  from  the  well.  After  part  of 
the  gas  pressure  is  released,  the  curve  representing  the  decline  of  prac- 
tically any  well,  unless  changed  by  some  mechanical  accident,  trends 
only  slightly  downward  at  a  rate  decidedly  less  than  its  previous  rate  of 
decline. 

VOL.  LTV. 22. 


338  APPLICATION   OF   LAW   OF   EQUAL   EXPECTATIONS 

It  should  be  noted  that  the  entire  length  of  the  average,  or  family 
curve,  as  shown  by  the  heavy  line  in  Fig.  1,  is  the  result  of  the  plotting  of 
past  production.  Sufficient  data  are  usually  available  so  that  the  curve 
can  be  carried  even  to  the  point  representing  minimum  economic  pro- 
duction, so  that  the  necessity  of  projecting  the  curve  to  represent  pro- 
duction in  the  future  is  obviated.  The  family  curve  in  this  case  is  based 
absolutely  on  actual  performance.  The  objection  to  some  curves  is 
the  necessity  of  projecting  them,  the  projection  in  many  cases  varying  with 
the  person  who  makes  it.  This  is  not  true,  however,  with  the  family 
curve,  especially  when  the  records  of  several  wells  representing  different 
outputs  are  available. 

In  a  new  field,  such  as  the  Montebello  field,  it  might  be  found  ad- 
vantageous to  construct  a  curve  with  a  monthly  time  interval  as  the 
horizontal  scale.  Then  with  wells  but  a  few  months  old,  a  family  curve 
may  be  prepared  with  but  little  difficulty. 

Another  method5  of  preparing  a  family  curve  is  to  divide  the  produc- 
tion records  into  classes  representing  different  productivity.  The  yearly 
output  of  all  wells  in  the  highest  class  (those  that  made  110,000  to  120,000 
bbl.  the  first  year)  is  averaged;  then  the  yearly  output  of  the  next  highest 
class  (those  that  made  100,000  to  110,000  bbl.  the  first  year)  is 
averaged,  and  the  average  points  plotted  and  so  on  until  all  the  aver- 
ages are  obtained. 

USE  OF  FAMILY  CURVE 

Because  wells  of  different  size  decline  along  the  same  type  curve, 
the  work  of  making  estimates  of  future  production  is  greatly  simplified. 
The  life  of  the  average  well  can  also  be  quickly  determined  and  the  limits 
of  decline  may  be  shown  graphically.  Furthermore,  the  future  yearly 
production  of  a  well  of  any  output  may  be  read  directly  from  the  average 
family  curve. 

FUTURE  PRODUCTION  CURVES 

In  Fig.  2,  curve  A,  above  the  family  curve  B,  was  determined  by 
adding  the  future  production  of  wells  of  different  output  as  shown  by 
the  family  curve  and  then  plotting  these  future  production  estimates 
vertically  above  the  point  on  the  family  curve  representing  the  first 
year's  production  of  a  well.  For  instance,  assume  a  point  on  the  family 
curve,  representing  21,000  bbl.  to  be  the  first  year's  production  of  a 
well  of  that  output.  The  second  year's  production  will  be  one  year 
to  the  right,  the  third  year's  production  two  years  to  the  right,  etc., 
to  the  point  of  minimum  economic  production.  These  estimated  annual 
productions,  with  the  exception  of  the  first  year,  as  shown  on  the  family 

6  Carl  H.  Deal:    U.  S.  Bureau  of  Mines  BuU.  177  (1919)  198,  and  Fig.  80. 


CARL   H.   BEAL   AND   E.    D.   NOLAN 


339 


curve,  are  added  together  and  plotted  vertically  above  the  point  on  the 
family  curve  representing  the  first  year's  production,  and  a  curve  A  drawn 
through  the  points.  In  the  present  instance,  the  yearly  production,  as 
represented  by  the  family  curve,  is  as  follows: 


YEAR 

1 

2 
3 

4 
5 


PRODUCTION, 
BARRELS 

21,000 

15,000 

11,500 

9,000 

7,000 


YEAR 
6 

7 
8 
9 


Total 


PRODUCTION, 
BARRELS 

5,500 

4,000 

2,000 

1,000 

76,000 


„;  leu.wu 
g 

*^  14.0  000 

\ 

* 

£ 

"o 

\ 

§  120,000 
o 

3 
o  1  00  000 

\ 

\ 

\ 

§ 

\ 

\ 

"g     80,000 

h 

1 
a  60  000 

\ 

\ 

\ 

(3 
5 

i2  /in  ooo 



-\ 

<  

\ 

\ 

r<- 

^ 

"IH    on  ri/in 

x 

^ 

i 

!  *  * 

^ 

^ 

^D0/, 

C8    ^O.OUO 
• 
>• 

S       o 

**         j 

L2      ~~1 

i     ~~i 

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j         s 

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i 
J  

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7              ( 

Jurve^ 

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~ 

•-> 

£***« 

--^ 

4 

**•  
d             \ 

== 

I 

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1           0 

Remaining  Life  of  Well,  (Years  ) 

FIG.  2. — AVERAGE  FUTURE  PRODUCTION  AND  "  FAMILY  "  CURVES  OF  A  CALIFORNIA 

OIL  FIELD. 

The  average  ultimate  production  of  the  well  will  be  76,000  bbl., 
and  the  future  55,000  bbl.  (76,000-21,000).  The  future  production, 
55,000  bbl.,  is  plotted  vertically  above  the  point  on  the  family  curve 
representing  21,000  bbl.  Because  of  the  law  of  equal  expectations, 
the  production  of  21,000  bbl.  could  represent  the  most  recent  years' 
production  if  desired;  that  is,  suppose  the  well  during  1918,  its  third 
year,  produced  21,000  bbl.  Then  if  the  well  is  an  average  well,  it  will 
produce  55,000  bbl.  from  1919  to  1926,  inclusive,  and  it  produced  30,000 
and  45,000  bbl.  during  1917  and  1916,  respectively. 

By  the  use  of  curve  A,  the  future  production  of  a  well  at  any  period 
of  its  life  may  be  determined  by  selecting  the  production  for  the  last 


340  APPLICATION  OP  LAW   OP  EQUAL  EXPECTATIONS 

year.  Find  this  amount  on  the  left  margin  and  trace  the  line  to  the 
right  to  a  point  where  it  intersects  the  family  curve,  follow  the  vertical 
line  through  this  point  upward  to  its  intersection  with  the  future  produc- 
tion curve,  thence  to  the  left  margin  of  the  figure.  The  reading  is  the  future 
production  of  the  well  selected.  For  example,  take  a  well  that  made 
20,000  bbl.  during  the  first  year,  follow  the  horizontal  line  to  the  right 
to  its  intersection  with  the  family  curve,  thence  upward  to  its  inter- 
section with  the  future  production  curve  and  thence  to  the  left  margin 
where  53,000  bbl.  is  indicated  as  the  average  future  production  of  a  well 
of  that  output.  The  estimate  would  have  been  correct  if  the  production 
of  20,000  bbl.  represented  the  most  recent  year's  production  instead  of 
the  first  year's  production. 

DETERMINING  AVERAGE  LIFE  OF  WELLS  OF  DIFFERENT  SIZE 

In  the  lower  margin  of  Fig.  2  will  be  found  figures  that  decrease  to  the 
right.  These  figures  represent  the  remaining  average  life  of  wells  and 
are  determined  by  counting  the  years  of  remaining  life  for  wells  of  differ- 
ent output,  as  shown  by  the  family  curve.  For  instance,  the  remaining 
life  of  the  well  that  made  20,000  bbl.  during  the  first  year,  by  reading 
downward  on  the  vertical  line  passing  through  the  point  on  the  family 
curve  representing  20,000  bbl.,  is  found  to  be  8  years.  From  this  curve, 
it  is  evident  that  the  lives  of  oil  wells  vary  directly  as  the  volume  of 
production,  for  the  larger  the  production,  the  longer  the  remaining  life. 

ULTIMATE  PRODUCTION  CURVES 

If  desired,  the  future  production  may  be  added  to  the  last  year's  pro- 
duction, which  will  give  the  ultimate  production  direct.  These  statistics 
may  be  plotted  for  wells  of  different  size  and  curves  thus  constructed. 
Both  this  and  the  average  future  production  curves  may  be  plotted  if 
desired,  although  the  ultimate  production  may  readily  be  obtained  by 
first  determining  the  future  production  and  adding  to  it  the  past  year's 
production. 

ANOTHER   METHOD   OF   SHOWING   FUTURE   PRODUCTION   CURVE 

The  curve  representing  future  production  may  be  expressed  as  an 
average  appraisal  curve  if  desired.  The  appraisal  curve  was  named  by 
Lewis  and  Beal,6  and  consists  of  showing  the  relation  between  the  first 
year's  production  of  a  well  and  its  ultimate  production.  The  suggestion 
was  made  that  additional  curves  showing  the  actual  future  could  be 
plotted  by  subtracting  from  the  ultimate  production  the  past  year's 


Trans.  (1918)  69,  492. 


CARL   H.   BEAL   AND   E.    D.   NOLAN 


341 


production.  The  future  production  curve,  as  arrived  at  by  the  family 
curve,  may  be  expressed  in  the  same  way;  that  is,  the  past  year's  pro- 
duction may  be  used  as  the  abscissa  and  the  future  production  may  be 
shown  as  the  ordinate.  In  this  way,  the  curve  begins  a  distance  to  the 
right  of  the  lower  left-hand  corner,  which  represents  the  minimum  eco- 
nomic production  to  which  the  average  well  in  a  district  can  be  pumped, 
and  rises  gradually  to  the  right,  having  the  same  form  as  appraisal  curves. 
There  is  no  particular  advantage  in  this  form  of  curve  over  curve  A, 
Fig.  2,  which  likewise  represents  future  production  directly. 

ERRATIC  WELLS 

In  any  field,  certain  wells  will  be  found  having  a  decline  wholly  differ- 
ent from  that  of  the  family  curve  of  that  group;  these  usually  are  con- 


120.000 

\ 

100,000 

3 
PQ 

\ 

^  80,000 
u 

1 

VB 

Jj  60,000 

5 
g 

0 

\> 

v^ 

o  40,000 

v    X^4 

i 

A, 

I 

v        >H 

V— 

[^ 

^^ 

S 
\           ,' 

A, 

^3 

20,000 

-Sr^-^ 

T—  -BT 
~t>-.. 

BS    " 

-S? 

^ 

B,B 

h 

- 

A* 

- 

— 

—  - 

12 

LI            1 

0 

y 

3 

I 

6 

5 

1 

3 

2 

1             C 

Remaining  Life  of  Well,  (Years) 

FIG.  3. — PRODUCTION  OF  ERRATIC  WELLS  PLOTTED  ON  "FAMILY"  CURVE  TO  SHOW 
THAT  SUCH  WELLS  USUALLY  DECLINE  ALONG  SOME  PART  OF  THE  CURVE  AFTER  ERRATIC 
PERIOD  ENDS;  RECORDS  INDICATED  BY  A  AND  B  ARE  WELLS  IN  CALIFORNIA  FIELD. 

sidered  abnormal  wells.  The  causes  of  these  wells  may  be  divided 
roughly  into  three  classes — geological,  accidental,  and  lack  of  histories 
of  wells.  Geological  causes  may  be  either  a  very  thick  series  of  oil  sands 
with  varying  gas  pressures  or  the  comparatively  sudden  invasion  of  edge 
water.  In  certain  small  districts,  such  as  the  area  in  Sec.  27f  T.  19  S., 
R.  15  E.  in  the  Coalinga  field,  or  that  near  Fellows  in  the  North  Midway 
field,  the  thickness  of  oil-bearing  series  is  from  500  to  70Q  ft.  (152.4  to 
213.3  m.).  Wells  drilled  through  this  thick  series  of  alternating  oil  sands 
and  shales  often  show  an  increasing  production  for  2  or  3  years  after 
inception.  After  having  reached  their  maximum,  however,  their  de- 
cline follows  the  family  curve.  The  probable  explanation  of  this  increase 
is  as  follows:  Such  wells  penetrate  a  number  of  rich  oil  sands,  but  under 


342  APPLICATION   OF   LAW   OF  EQUAL  EXPECTATIONS 

varying  gas  pressures.  When  first  brought  in  only  those  sands  with  the 
higher  gas  pressures  are  able  to  produce  but  time  permits  a  lessening  and 
readjusting  of  the  pressures  and  all  sands  are  able  to  contribute  to  the 
well's  production.  Curve  A,  Fig.  3,  shows  the  production  of  a  well  of 
this  type  and  its  relation  to  the  family  curve.  Wells  producing  from  a 
sand  suddenly  invaded  by  water  may  show  an  increase  in  production  just 
prior  to  the  appearance  of  the  water,  but  almost  invariably  show  a 
rapid  decline  and  a  sudden  end. 

Accidental  causes  of  erratic  wells  might  also  be  called  mechanical 
causes.  The  "oil  string"  may  collapse,  shutting  off  its  production,  or 
a  redrilling  job  may  be  a  failure,  causing  the  abrupt  ending  of  the  well's 
life.  In  the  loose  unconsolidated  sands  of  the  California  fields,  shale 
may  cave  in,  shutting  off  the  perforations.  These  accidents  usually 
cause  a  sharp  break  in  the  decline  of  the  well  and  a  consequent  dropping 
away  from  the  family  curve.  After  this  initial  break,  its  decline  through 
the  remainder  of  its  life  usually  follows  some  other  part  of  the  family 
curve.  The  decline  indicated  by  B,  Fig.  3,  is  of  such  a  well. 

Another  class  of  erratic  wells  that  often  cause  trouble  are  those  that 
have  been  deepened.  When  a  well  is  deepened  into  lower  sands  or  is 
redrilled,  with  a  consequent  opening  of  new  sands,  or  possibly  shutting 
off  other  oil  sands,  it  must  be  treated  as  a  new  well,  and  accordingly  a 
new  part  of  the  family  curve  selected  as  its  decline  curve. 

Wells  varying  from  the  family  curve  sufficiently  to  be  termed  erratic 
wells  are  rare,  certainly  less  than  10  per  cent,  of  the  total  wells  in  the  Cali- 
fornia fields.  The  divergence  in  most  erratic  wells  takes  place  during 
the  first  2  or  3  years  of  the  life  of  the  well.  From  that  time  on,  the  out- 
put of  the  well  follows  some  part  of  the  family  curve. 

ESTIMATING  FUTURE  PRODUCTION  OF  WELLS  ABOVE  AND  BELOW  THE 

AVERAGE 

Most  wells  in  a  field  will  follow  the  family  curve  with  fair  exactness. 
Some  will  trend  slightly  above  it,  follow  it  for  a  year  or  so,  and  finally 
fall  below.  One  is  usually  safe,  however,  in  making  estimates  of  the 
future  production,  if  he  assumes  the  well  to  be  an  average  well;  he  is 
unwise,  however,  if  he  makes  no  effort  to  determine  the  amount  a  well 
is  above  or  below  the  average,  for  if  it  deviates  far  from  the  average  the 
estimate  may  and  should  be  modified  accordingly.  Fortunately,  as 
most  estimates  of  future  production  are  made  by  using  the  last  year's 
production,  the  curve  tends  to  correct  itself  by  automatically  shifting 
the  point  on  the  family  curve  at  which  the  estimate  is  made  to  the  right 
or  left,  according  to  whether  the  curve  is  below  or  above  the  average. 
This  may  be  more  clearly  shown  by  taking  an  example.  Suppose  well 
A,  Fig.  3,  has  produced  2  years,  as  shown  by  A  and  A\\  the  estimate  of 


CARL   H.  BEAL  AND   E.   D.   NOLAN  343 

future  production  is  made  by  applying  the  last  year's  production  (indi- 
cated by  AI)  to  the  family  curve,  thus  shifting  the  point  AI  to  the  left 
to  where  a  horizontal  line  through  it  intersects  the  family  curve.  As 
subsequent  production  from  this  particular  well  has  proved  (see  points 
A' 2,  A '3  and  A'4),  the  estimate  of  future  production  would  have  been 
slightly  above  the  average  curve. 

Another  example  will  serve  to  show  the  method  by  which  the  esti- 
mates of  future  production  of  wells  below  the  average  will  tend  to  correct 
themselves.  Suppose  well  B,  Fig.  3,  has  produced  2  years  (B  and  BI), 
an  estimate  of  its  future  production  will  be  made  from  point  B\  on  the 
family  curve.  Subsequent  production  would  indicate  that  the  well  pro- 
duced along  a  curve  (B'z,  B'$  and  J5'4)  almost  coincident  with  the  family 
curve.  If  estimates  are  made  yearly,  they  become  closer  and  closer  even 
though  the  well  may  produce  along  a  curve  considerably  above  or  below 
the  average. 

FAMILY  CURVE  APPLIED  TO  TRACT  OR  PROPERTIES  PRODUCTION 

Where  the  individual  well  records  are  lacking  or  where  the  average 
well  production  is  quite  small,  it  may  be  either  necessary  or  convenient 
to  construct  a  family  curve  for  a  group  of  tracts  rather  than  for  a  group 
of  individual  wells.  Such  curves  when  constructed  from  a  number  of 
properties  and  applied  to  properties  that  are  sufficiently  drilled  are  quite 
accurate. 

VALUE  OP  FAMILY  CURVE 

The  greatest  advantage  of  the  family  curve  is  the  fact  that  it  is  based 
entirely  on  history;  it  usually  has  no  projections  and  it  is  not  difficult  to 
prepare.  Furthermore,  its  advantage  over  the  appraisal  curve  is  that  it 
can  be  prepared  with  less  data.  In  fact,  the  statistics  representing 
the  decline  of  a  dozen  wells  might  suffice  for  the  preparation  of  a  curve, 
the  decline  of  which  represents  the  decline  of  wells  of  different  size  in  an 
area  where  conditions  affecting  production  are  practically  equivalent. 
The  accuracy  of  the  curve,  however,  is  increased  in  direct  proportion 
to  the  number  of  records  used  in  its  preparation. 

Another  advantage  over  appraisal  curves  is  that  the  future  produc- 
tion of  a  well  from  its  first  year  can  be  estimated  more  readily  when  the 
decline  of  the  well  is  above  or  below  the  average.  Owing  to  the  fact  that 
the  last  year's  production  is  used  and  that  erratic  wells  after  their  abrupt 
change  follow  a  portion  of  the  family  curve,  the  curve  reduces  error  to  a 
small  amount,  and  tends  to  correct  errors  due  to  its  own  limitations. 
The  simplicity  and  completeness  of  the  curve  are  the  principal  arguments 
in  its  favor.  One  may  read  direct  the  future  production  of  a  well,  its 
probable  life  in  years  and  its  probable  production  in  any  year  in  the 
future. 


344  ESSENTIAL   FACTORS   IN  VALUATION   OF   OIL   PROPERTIES 


Essential  Factors  in  Valuation  of  Oil  Properties* 

BY  CARL  H.  SEAL,!  M.  A.,  SAN  FRANCISCO,  CALIF. 

(Chicago  Meeting,  September,  1919) 

THE  most  important  factors  that  should  be  given  consideration  in 
the  valuation  of  oil  lands  are:  (1)  the  amount  of  oil  the  property  will  pro- 
duce; (2)  the  amount  of  money  this  oil  will  bring  (based  upon  the  future 
prices  of  oil);  (3)  development  and  production  costs;  (4)  the  rate  of  in- 
terest on  the  investment;  (5)  the  retirement  or  amortization  of  invested 
capital;  and  (6)  the  salvage  or  "  scrap  "  value  of  the  equipment  when  the 
property  is  exhausted.  These  factors  are  of  varying  importance  and 
some  of  them  may  not  enter  all  valuation  problems,  but  most  of  them 
should  be  given  consideration  in  any  valuation  even  though  only  a  rough 
estimate  of  the  value  of  the  property  is  desired. 

The  value  of  a  property  may  be  changed  over  night  by  the  completion 
of  important  test  wells,  by  the  sudden  water  flooding,  or  by  a  change  in 
the  price  of  oil.  The  best  a  petroleum  engineer  can  give  is  the  value  of 
the  property  under  the  conditions  existing  at  the  time  the  appraisal  is 
made  with  a  fair  forecast  of  future  action  of  the  wells  and  of  the  price  of  oil. 

Our  experience  in  the  scientific  valuation  of  oil  lands  is  not  broad  and 
there  is  very  little  published  information  on  the  subject;  it,  therefore, 
becomes  necessary  in  studying  such  problems  to  form  comparisons  with 
the  factors  involved  in  the  valuation  of  mines — the  closest  parallel. 
One  of  the  reasons  for  the  lack  of  substantial  progress  in  oil-land  valua- 
tion methods  has  been  the  necessity  of  making  an  estimate  of  the 
future  production  of  the  oil  property  to  be  valued.  Oil  men  and  ac- 
countants have  not  generally  conceded  that  such  estimates  could  be 
made  with  any  degree  of  accuracy.  It  has  been  shown,  however,  in 
several  recent  publications  that  with  certain  data  available  reasonably  close 
estimates  can  be  made.  The  accuracy  of  an  appraisal  depends  chiefly 
on  the  accuracy  of  the  estimates  of  future  production  and  of  the  future 
price  of  oil.  The  accuracy  of  the  former  is  sometimes  necessarily  based 
on  geological  inferences.  Geology  is  not  an  exact  science  and  geological 
data  in  connection  with  oil  production  cannot  always  be  mathematically 
evaluated. 


*  Published  by  permission  of  Director,  U.  S.  Bureau  of  Mines, 
t  Petroleum  Technologist,  U.  S.  Bureau  of  Mines. 


CARL  H.  BBAL  345 

FUTURE  OIL  OR  EXPECTATION 

In  considering  the  factor  of  future  oil,  two  related  questions  must  be 
answered:  How  much  oil  will  the  property  produce?  At  what  rate  will 
the  oil  be  produced?  If  we  can  determine  the  future  annual  production 
of  an  oil  property,  we  may  easily  determine  the  total  future  production 
by  addition,  so  we  will  consider  only  the  question  of  rate  of  future  oil 
production. 

A  satisfactory  answer  to  this  question  is  the  keynote  to  the  whole 
valuation;  for,  although  our  work,  has,  by  no  means,  been  completed 
after  the  question  has  been  disposed  of,  the  work  of  determining  the  value 
of  the  property  is  greatly  simplified,  for  on  the  yearly  output  of  oil  depends 
the  yearly  gross  income.  From  the  gross  income  the  annual  net  return 
is  computed,  each  year's  return  being  considered  in  the  light  of  a  profit 
available  at  a  future  date.  The  present  value  of  these  deferred  profits 
is  then  determined  by  discounting  them  at  a  rate  of  interest  compatible 
with  the  risk  involved. 

No  uniform  yearly  revenue  can  usually  be  expected  from  an  oil  prop- 
erty, for  the  annual  output,  and  thus  the  annual  income,  depends  on 
the  rate  of  production.  Only  under  exceptional  conditions  can  a  steady 
oil  production  be  maintained  for  long  unless  the  property  is  old  and  pro- 
duction well  settled.  The  future  annual  oil  output  hinges  on  the  rapidity 
with  which  new  wells  are  drilled  and  on  the  rate  of  production  of  the 
individual  wells  which,  with  very  few  exceptions,  always  declines. 

Rate  at  Which  Oil  Will  Be  Obtained. — The  rate  of  production  of  the  wells 
will  affect  not  only  the  rate  of  output  of  the  old  wells,  but  will  regulate 
that  of  the  wells  to  be  drilled.  Furthermore,  the  decline  in  the  initial 
output  must  be  considered;  the  longer  the  development  of  the  proved 
acreage  is  deferred,  the  less  will  be  its  ultimate  production,  for,  under 
usual  conditions,  the  wells  on  the  drilled  acreage  cause  a  decrease  in  gas 
pressure  over  the  undrilled  acreage,  which  results  in  decreased  initial 
production  of  the  wells  eventually  drilled  there.  The  rate  at  which  oil 
wells  will  produce  is  the  resultant  of  many  complex  factors,  which  will 
not  be  discussed  here.  For  more  information  on  this  subject,  the  reader 
is  referred  to  a  bulletin  by  the  author.1 

The  most  trustworthy  method  of  determining  the  rate  of  production 
of  the  wells  of  a  group  is  to  prepare  a  production  curve  that  will  give  the 
average  yearly  output  of  wells  of  different  initial  yearly  output.  It  is 
necessary  to  determine  this  for  wells  of  different  initial  production,  be- 
cause wells  of  different  output  decline  in  production  at  different  rates — 
other  factors  being  equal. 

1  Carl  H.  Beal:  Decline  and  Ultimate  Production  of  Oil  Wells  with  Notes  on  the 
Valuation  of  Oil  Properties.  U.  S.  Bureau  of  Mines  Butt.  177  (1919). 


346  ESSENTIAL  FACTORS   IN  VALUATION   OF  OIL  PROPERTIES 

Drilling -Program. — The  rate  of  the  production  of  the  property  depends 
not  only  on  the  rate  at  which  the  individual  wells  will  produce  oil  but  also 
on  the  rapidity  with  which  new  wells  are  added  to  the  producing  list; 
this  depends  on  the  drilling  program.  The  valuation  should  not  be 
attempted  until  a  drilling  program  is  decided  upon.  But  before  a  drill- 
ing program  can  be  determined,  it  is  necessary  to  know  the  amount  of 
land  that  certainly  will  support  commercially  productive  wells ;  trust- 
worthy estimates  of  future  oil  production  can  be  made  only  for  the  drilled 
acreage  and  for  the  undrilled  proved  acreage.  Only  such  land  furnishes 
a  concrete  basis  of  value,  for  the  annual  production  of  oil  can  be  esti- 
mated; other  land  has  a  speculative  value  that  varies  with  the  uncertainty 
of  obtaining  oil  in  commercial  quantities.  These  tracts,  if  included, 
should  be  valued  separately  and  on  a  different  basis. 

Although  there  is  no  case  exactly  parallel  in  metal  mining,  the  metal- 
mining  engineer  refuses  to  commit  himself  on  the  value  of  a  prospective 
mine.  The  petroleum  engineer  may  determine  the  magnitude  of  the 
risk  and  compute  mathematically  the  probability  of  obtaining  oil  on  a 
tract  of  land;  but  the  author  is  inclined  to  agree,  in  a  measure,  with 
Rickard2  that  "the  doctrine  of  probabilities  has  been  stultified  too 
often  to  allow  of  its  being  stated  as  a  scientific  thesis. " 

In  valuing  the  proved  oil  land,  the  engineer  should  compute  the 
value  of  the  output  of  the  property  based  on  a  drilling  program  that 
will  bring  the  maximum  return  in  profits  to  the  investor.  It  is  true 
that  a  variation  in  the  drilling  program  sometimes  will  greatly  reduce 
the  profits  eventually  gained  from  a  property,  but  there  can  be  only 
one  maximum  value  and  this  is  the  one  to  be  determined. 

CLASSIFICATION  OF  LAND  TO  BE  VALUED 

Before  the  future  annual  production  can  be  estimated,  it  is  necessary 
to  classify  the  land  to  be  valued,  to  determine  the  amount  of  acreage 
that  will  support  new  wells.  For  this  purpose  the  land  is  first  divided 
into  drilled  and  undrilled.  These  two  classes  of  acreage  must  be  valued 
separately. 

Estimating  the  future  production  of  the  old  wells  usually  is  not 
difficult,  if  production  curves  are  available.  Our  greatest  difficulty 
lies  in  making  estimates  of  the  probable  future  production  of  the  proved 
undrilled  acreage.  Here  we  must  be  guided  by  underground  geologic 
conditions  and  by  what  the  new  wells  probably  will  produce  by  comparing 
the  conditions  under  which  they  are  to  produce  with  the  conditions 
under  which  the  nearby  old  wells  are  producing.  The  undrilled  oil 


1 T.  A.  Rickard:  Valuation  of  Metal  Mines.    International  Engineering  Congress, 
1915. 


CARL   H.   BEAL  347 

land  may  usually  be  divided  into  the  following  four  general  classes: 
Proved  acreage,  probable  acreage,  prospective  acreage,  and  commercially 
non-productive  acreage.  Some  engineers  use  much  more  detailed 
classifications.  These,  the  writer  believes  incompatible  with  the  un- 
certainty of  underground  conditions.  The  following  definitions  are 
advanced  tentatively: 

Proved  acreage  should  include  that  in  which  drilling  involves  practi- 
cally no  risk.  The  following  definition  is  proposed,  which  has  been 
modified  from  that  given  by  R.  P.  McLaughlin.3  "  Proved  oil  land  is 
that  which  has  been  shown,  by  finished  wells  supplemented  by  geologic 
data,  to  be  such  that  other  wells  drilled  thereon  are  practically  certain  to 
be  commercial  producers." 

Probable  oil  land  includes  those  areas  generally  adjacent  to  produc- 
ing oil  and  gas  wells  where  the  existence  of  oil  is  not  proved,  but  where 
geologic  evidence  indicates  a  good  chance  of  obtaining  oil  in  commercial 
quantities. 

Prospective  oil  land  includes  those  areas  usually  not  adjacent  to 
producing  oil  and  gas  wells,  where  the  existence  of  oil  is  not  proved,  but 
where  geologic  data  justifies  drilling  a  test  well.  Land  in  this  class  is 
distinguished  from  the  probable  oil  land  by  the  greater  uncertainty  of 
obtaining  oil  owing,  usually,  to  its  location  some  distance  from  producing 
oil  and  gas  wells. 

Commercially  non-productive  oil  land  is  that  on  which  commercially 
productive  wells  cannot  be  drilled  at  present.  The  existence  of  oil 
under  the  areas  of  this  class  may  be  proved,  probable,  or  prospective. 

Exceptions  undoubtedly  will  be  found  in  every  class.  For  instance, 
under  some  conditions,  a  person  may  feel  warranted  to  place  land  in  the 
probable  class  when  it  is  favorably  located  geologically,  even  though  it 
is  several  miles  from  producing  wells,  for  the  reason  that  the  occurrence 
of  oil  and  gas  with  relation  to  certain  geologic  structures  in  that  region 
may  be  so  certain  as  to  make  the  chance  of  not  obtaining  some  oil  very 
small.  Furthermore,  the  classification  of  land  may  change  rapidly, 
owing  to  the  drilling  of  new  wells,  damage  by  water,  or  change  in  price. 
For  example,  an  area  that  may  be  rated  as  commercially  non-productive 
may  become  commercially  productive  and  proved  with  an  increase  in 
the  price  of  oil. 

FUTURE  PRICE  OF  OIL 

The  accuracy  of  any  valuation  depends  on  the  price  that  is  to  be 
received  for  the  oil,  for  on  it  depends  the  net  profit  per  barrel  of  oil 
marketed.  A  small  variation  in  the  price  of  oil  may  mean  the  difference 

3  R.  P.  McLaughlin:  Petroleum  Industry  of  California.  California  State  Mining 
Bureau  Butt.  69  (1914)  13. 


348  ESSENTIAL   FACTORS   IN  VALUATION   OF   OIL   PROPERTIES 

between  gain  or  loss.  In  fact,  since  the  working  out  of  new  and  more 
trustworthy  methods  for  more  accurately  estimating  future  oil  produc- 
tion, the  estimation  of  the  future  price  has  become  one  of  the  most  uncer- 
tain elements  to  be  contended  with  in  oil  land  valuation. 

The  engineer,  to  make  sound  predictions  as  to  the  probable  price  of 
oil,  even  during  the  immediate  future,  must  possess  a  broad  knowledge 
of  the  petroleum  situation  as  regards  supply  and  demand.  Either 
prices  will  be  allowed  to  adjust  themselves  in  accordance  with  the  law 
of  supply  and  demand,  or  they  will  be  manipulated  by  monopolies  or 
controlled  by  the  Federal  Government.  If  manipulation  or  government 
control  exists,  or  if  there  is  a  strong  probability  of  their  coming  into 
existence,  the  engineer  should  be  guided  accordingly.  Otherwise,  the 
question  of  price  must  be  answered  solely  by  the  domestic  and  foreign 
oil  situation.  The  past  range  of  prices  has  often  been  great,  but  the 
future  probably  will  never  see  such  low  prices  of  oil.  The  market  is 
now  more  stable  because  the  demand  for  the  commodities  made  of 
petroleum  is  greater  and  new  oil  fields  are  much  more  scarce  and  more 
costly  to  develop. 

The  reason  for  the  great  demand  for  oil  is  primarily  because  of  the 
great  demand  for  one  of  its  products — gasoline.  The  great  demand  for 
gasoline  is  created  by  the  phenomenal  development  of  the  internal- 
combustion  engine.  This  development  is,  probably,  by  no  means,  com- 
pleted. The  adoption  of  oil  as  fuel  by  the  great  navies  of  the  world  and 
the  development  and  adoption  of  the  Diesel  engine  have  greatly  increased 
the  demand  for  the  heavier  products  of  petroleum.  Very  likely  the 
future  demand  for  oil  and  its  products  will  not  decrease. 

The  upward  limit  of  prices  is  set  by  the  cost  of  importing  oil  and 
the-  cost  of  developing  a  supply  of  oil  from  oil  shales,  of  which  there  are 
immense  deposits  in  this  country.  By  considering  the  status  of  the  in- 
dustry at  the  present  time  and  these  two  limiting  factors,  the  engineer 
should  be  able  to  make  reasonably  sound  estimates  of  the  price  of  oil 
for  the  next  few  years.  Some  engineers  find  it  advisable  to  use  the  present 
prices  as  a  basis  of  estimating  the  value  of  the  property  or  to  determine 
the  value  of  the  property  at  several  different  prices  of  oil,  and  thus  allow 
the  investor  to  select  the  one  that,  in  his  judgment,  will  best  meet  future 
conditions. 

COST  OF  PRODUCTION  AND  DEVELOPMENT 

In  determining  the  future  net  receipts  from  each  barrel  of  oil,  the 
cost  of  producing  the  oil  must  be  subtracted  from  the  gross  income  or 
selling  price.  For  the  purpose  of  estimating  future  production  costs, 
including  drilling  charges,  tankage,  and,  in  fact,  every  charge  that  con- 
tributes to  the  final  total  cost  of  production,  the  appraiser  should  refer  to 
trustworthy  statistics  and  should  be  able  to  interpret  these  statistics  in 


CARL  H.  BEAL  349 

terms  of  probable  future  conditions.  This,  again,  requires  not  only  a 
broad  knowledge  of  the  oil  industry  but  also  detailed  knowledge  of  costs 
in  the  locality  where  the  property  is  situated. 

INTEREST  ON  INVESTMENT 

The  proper  rate  of  interest  to  be  received  from  an  investment  must 
be  such  that  capital  will  be  attracted  to  the  enterprise.  If  the  risk 
attached  to  the  investment  is  great,  the  rate  of  interest  on  the  money 
invested  must  be  high  or  investors  cannot  be  found.  The  returns  from  oil 
investments  are  always  speculative  to  some  degree,  so  the  interest 
demanded  is  usually  high.  If  there  is  no  risk,  the  investor  can  afford  to 
invest  his  money  at  the  same  rate  as  if  he  put  it  in  the  savings  bank  at  4 
per  cent. 

The  basis  of  value  in  oil. lands  is  net  income.  The  net  income  for 
each  future  year  of  the  productive  lif e  of  the  oil  property  must  be  estimated 
and  these  future  values  compared  with  their  real  values  at  the  present 
moment  by  reducing  them  to  present  value  at  a  given  rate  of  interest. 
This  is  discount  and  is  the  reverse  of  compound  interest,  the  factor  used 
in  the  reduction  of  future  values  to  present  values  being  called  the  dis- 
count factor,  which  is  a  very  important  element  in  oil-land  valuation. 
By  the  reverse  of  discount,  or  compound  interest,  the  future  value  of  a 
present  income  may  be  determined. 

Present  value  of  a  future  income  may  be  defined  as  that  sum  which, 
when  placed  at  interest  at  a  stated  per  cent.,  will  equal  the  income  at  the 
date  when  it  is  to  be  realized.  Thus,  the  longer  the  deferment  of  an 
income  the  less  it  is  worth  at  the  present  time,  for  which  reason  one  can 
afford  to  pay  more  for  income  to  be  obtained  from  the  oil  from  a  well 
drilled  now  than  for  the  same  well  drilled  a  year  hence,  providing  the  price 
of  oil  remains  constant  and  equal  amounts  of  oil  are  produced.  Further- 
more, the  longer  drilling  is  postponed  the  less  the  net  proceeds  from  the 
wells  are  worth  to  a  prospective  purchaser  at  the  present  time.  Other 
things  being  equal  a  property  should  be  drilled  as  quickly  as  possible,  if 
the  maximum  income  is  to  be  derived  from  it.  This  may  not  be  best 
from  the  standpoint  of  the  public,  and,  if  generally  practiced  by  oil 
producers,  would  eventually  work  to  their  advantage. 

The  interest  required  on  the  investment  must  be  high  because  risk 
is  attached  to  the  venture.  Some  engineers  consider  that  the  discount 
used  in  reducing  future  income  to  present  value,  however,  should  not 
be  compounded  for  the  reason  that  to  compound  a  certain  present  sum 
to  determine  its  future  value  means  the  first  year  to  determine  the 
interest  on  the  principal  and  thereafter  to  compute  yearly  the  interest  on 
the  principal  and  accumulated  interest  earnings.  The  rate  used  is  a 
high  rate  because  the  capital,  or  principal,  is  being  risked.  This  rate 


350  ESSENTIAL   FACTORS   IN  VALUATION   OF   OIL   PROPERTIES 

should  not  be  applied  to  the  accumulated  interest  earnings,  however, 
because  these  are  not  risked  capital.  They  are  earnings  and  should 
be  considered  as  such. 

The  computed  maximum  value  of  the  property  may  be  considerably 
less  than  what  actually  could  be  paid  for  the  property  for  as  the  returns 
in  the  investment  are  realized  they  may  be  reinvested  in  gilt-edged 
securities  at  an  accumulative  rate  of  interest. 

AMORTIZATION  OF  INVESTMENT 

In  investing  in  an  exhaustible  resource,  the  investor  expects  not 
only  the  return  of  a  certain  interest  on  the  investment,  but  also  the 
return  of  the  principal  by  the  time  the  resource  is  exhausted.  This  is 
called  amortization,  or  retirement  of  capital,  and  may  be  effected  by  a 
sinking  fund  into  which  annual  contributions  are  made.  The  sinking 
fund  may  be  placed  at  interest,  so  that  the  sum  of  the  annual  contri- 
butions may  not  be  required  to  equal  the  total  original  capital.  Although 
sinking  funds  may  not  be  established,  some  attempt  must  be  made  to 
return  capital  uniformly  and  justly,  where  it  is  possible  to  estimate  the 
amount  of  oil  recoverable  and  the  hazard  of  the  investment  is  not  too 
great  to  make  such  calculations  useless. 

A  method  often  practiced  by  oil  companies  to  determine  the  rate  of 
retiring  the  capital  invested  in  both  physical  property  and  in  the  re- 
source is  called  the  "settled  production  method,"  and  consists  of  apply- 
ing a  unit  value  per  barrel  of  settled  daily  production.  The  value  of 
the  property  at  any  time  is  the  daily  production  mutiplied  by  the  unit 
value.  The  difference  in  the  value  determined  at  any  two  periods  is  the 
depreciation  or  appreciation  according  to  whether  the  value  has  gone 
down  or  up. 

A  modification  of  this  method  for  the  purpose  of  determining  the 
depletion  deduction  in  connection  with  the  computing  of  taxable  income, 
is  called  the  "reduction  in  flow  method."  The  method  has  been  author- 
ized by  the  Treasury  Department,  but  obviously  is  unfair,  when  it  is 
remembered  that  the  basis  of  the  method  depends  on  a  reduction  in  the 
output  of  an  oil  property  from  the  existing  wells  only.  No  depletion  is 
allowed  and,  therefore,  no  capital  is  retired  unless  production  is  decreas- 
ing. If  production  decreases  5  per  cent,  during  the  taxable  year,  5  per 
cent,  of  the  capital  invested  is  retired.  During  the  next  year,  if  the 
decrease  is  10  per  cent.,  that  percentage  of  the  unretired  capital  is 
"  written  off."  As  a  general  rule,  the  output  of  an  oil  property  increases 
for  a  few  months,  at  least,  while  drilling  of  new  wells  is  in  progress,  and 
in  some  fields,  production  may  increase  for  several  years.  Still,  by  use 
of  this  method  no  capital  can  be  retired  until  the  production  of  the  tract 
begins  to  decrease.  Production  of  oil  means  depletion  of  its  recoverable 


CARL  H.   BEAL  351 

content  and  every  barrel  of  oil  taken  from  a  property  exhausts  it  just 
that  much,  and  brings  it  just  that  much  nearer  the  end  of  its  life.  To 
retire  no  capital  while  production  is  largest  and  then  when  production 
begins  to  decline,  to  retire  large  amounts  against  a  decreasing  income 
not  only  is  inequitable  to  the  oil  operator  but  places  the  whole  enterprise 
in  jeopardy  by  deferring  the  amortization  to  a  period  when  the  field  is 
rapidly  approaching  exhaustion  and  too  late  to  cover  the  return  of 
capital. 

The  producer  has  made  a  definite  investment  in  each  barrel  of  recover- 
able oil.  If  he  can  estimate  the  amount  of  recoverable  oil,  he  can  easily 
determine  the  cost  per  barrel.  For  every  barrel  of  oil  produced,  he 
should  retire  an  amount  of  capital  equal  to  the  original  investment  in 
that  barrel  of  oil.  This  is  called  the  "unit  cost  method,"  by  which  a 
fixed  charge  per  barrel  of  oil  produced,  based  on  quantity,  is  assessed. 
It  is  sound  in  principle,  not  difficult  of  application,  and  has  been  adopted 
by  the  Treasury  Department  in  the  determination  of  the  depletion 
deduction  in  connection  with  the  administration  of  the  income  and  excess- 
profits  tax  laws.  This  undoubtedly  is  the  fairest  and  most  equitable 
method  of  amortizing  an  investment  in  a  mineral  property.  The  method 
is  suggested  in  several  publications  on  mine  accounting,4  so  has  the  added 
weight  of  precedence. 

The  basis  of  this  method  is  to  determine  the  total  capital  invested  in 
the  oil  and  then  divide  the  estimated  recoverable  oil  into  the  capital 
invested ;  the  result  is  the  unit  cost.  For  instance,  if  the  sum  of  $1,000,000 
is  invested  in  the  oil  under  a  property,  estimated  to  produce  ulti- 
mately 10,000,000  barrels  of  oil,  the  unit  cost  per  barrel  is  10  c.  The 
producer  has  paid  this  sum  for  each  barrel  of  oil  under  the  property. 
If  he  sells  each  barrel  of  oil  for  $1.50,  his  net  income  for  each  barrel 
will  be  determined  by  deducting  all  charges  from  $1.50.  Suppose  all 
charges,  excepting  unit  cost,  amount  to  40  c.  per  barrel,  his  net  income 
is,  therefore,  $1. 

Estimates  of  future  production  may  be  revised  each  year  and  a  new 
"unit  cost"  obtained  by  dividing  the  unretired  capital  by  the  remaining 
recoverable  oil.  The  amount  of  capital  to  retire  during  that  year  on 
account  of  depletion  will  be  the  unit  cost  multiplied  by  the  production. 

Many  oil  companies  have  adopted  this  system  because  by  its  use  they 
are  enabled  not  only  to  determine  the  depletion  deduction  equitably  and 
justly,  but  also  because  they  are  enabled  to  retire  the  capital  investment 
at  the  same  rate  at  which  the  oil  is  produced.  The  only  unknown  factor 
in  the  determination  of  unit  cost  is  the  amount  of  recoverable  oil,  and 


4F.  Hobart  in  "The  Economics  of  Mining,"  by  T.  A.  Rickard  and  others,  223, 
1905. 


352  ESSENTIAL  FACTORS   IN  VALUATION   OP  OIL  PROPERTIES 

this  can  be  estimated  with  a  reasonable  degree  of  certainty  by  the  use  of 
methods  outlined  by  Lewis6  and  the  author.6 

Depreciation  refers  to  the  wear  and  tear  on  physical  property  and 
capital  invested  in  it  must  be  retired  in  addition  to  the  capital  invested 
in  the  exhaustible  resource.  The  methods  of  retiring  such  capital  will 
not  be  discussed  in  this  paper.  The  amount  retired  should  be  equal  to 
the  capital  invested  minus  the  salvage  or  "scrap"  value  of  the  equipment. 

SALVAGE  VALUE  OF  EQUIPMENT 

When  the  oil  is  exhausted,  a  certain  amount  of  physical  property  will 
be  on  hand.  The  investment  in  this  physical  property  should  have  been 
completely  amortized,  with  no  investment  remaining  except  that  which 
can  be  realized  from  the  disposal  of  the  equipment.  This  sum  is  called 
the  salvage,  or  "scrap/7  value  of  the  equipment.  Ordinarily  this  "junk" 
value  is  not  great  at  the  exhaustion  of  the  oil.  Furthermore,  the  pro- 
ceeds derived  from  the  sale  of  the  "junk"  must  be  discounted  to  the 
time  of  the  valuation  at  a  certain  rate  of  interest.  Usually  the  property 
will  have  a  life  of  more  than  20  years,  and  the  present  value  of  the  junk, 
even  at  a  comparatively  low  rate  of  interest,  is  rather  small  when  com- 
pared with  other  sources  of  income  that  must  be  present  before  the  invest- 
ment is  a  good  one.  Occasionally,  the  expenses  in  connection  with  the 
abandonment  of  the  property,  such  as  properly  plugging  the  wells,  will 
cost  as  much  or  more  than  the  present  value  of  the  junk,  so  that  this 
item  in  oil-land  valuation  is  ordinarily  not  important. 

6  J.  O.  Lewis  and  Carl  H.  Beal:  Some  New  Methods  for  Estimating  the  Future 
Production  of  Oil  Wells.     Trans.  (1918)  69,  492. 
« U.  S.  Bureau  of  Mines  Bull.  177. 


APPRAISAL   OP  OIL  PROPERTIES  353 


Appraisal  of  Oil  Properties 

BY  EARL  OLIVER,*  PONG  A  CITY,  OKLA. 

(New  York  Meeting,  February,  1920) 

THE  term  oil  property,  in  this  discussion,  includes  any  type  of  ease- 
ment or  grant  under  which  petroleum  might  be  produced;  it  ranges  from 
the  mere  right  to  drill  on  undeveloped  wildcat  acreage  up  to  a  fully 
developed  oil  property.  The  values  of  an  oil  property,  as  thus  defined, 
vary  widely  according  to  the  use  for  which  it  is  intended,  whether  it  is 
from  the  viewpoint  of  the  speculator,  the  fraudulent  stock  promoter, 
the  refiner  and  pipe-line  owner,  or  the  oil  producer. 

The  market  value  of  a  property  is  usually  a  combination  of  some 
two  or  more  of  these  influences,  and  occasionally  a  combination  of  all 
of  them,  but  we  prefer  to  treat  each  viewpoint  as  distinct  from  the  others, 
allowing  the  reader  to  make  his  own  combination  in  such  proportions 
as  his  inclination  and  property  seem  to  require.  This  paper  will  treat 
the  subject  from  the  viewpoint  of  the  oil  producer.  However,  the  other 
influences  have  such  bearing  on  the  cost  of  property  to  the  producer 
and  on  the  price  he  might  obtain  by  its  sale  as  to  warrant  brief  discussion 
of  them. 

Speculation,  particularly  lease  speculation,  is  a  parasitic  growth  on 
the  oil  industry,  healthy  enough,  but  of  no  economic  value.  The  class 
of  property  usually  dealt  in  for  this  purpose  is  the  undeveloped  lease. 
Its  speculative  value  may  have  some  relation  to  its  probable  productive 
value,  but  most  frequently  this  value  is  the  product  of  temporary 
excitement  due  to  local  development.  The  lease  speculator,  seeking  out 
the  trend  of  development  or  securing  early  information  regarding  a  pro- 
posed test  or  a  new  discovery,  immediately  secures  leases  whose  market 
value  will  be  increased  when  the  existence  of  such  development  becomes 
more  widely  known.  His  profits  are  purely  unearned  increment. 
Not  proposing  to  spend  money  in  exploration,  he  can  afford  to  compete 
in  purchase  with  the  operator,  who,  in  addition  to  bonus  paid,. must 
spend  large  sums  in  testing  out  his  own  acreage  and  that  of  the  nearby 
speculator  as  well.  It  has  a  tendency  to  compel  unduly  high  bonuses. 
The  so-called  "checker-board"  system  of  leasing  wildcat  acreage  by  the 
larger  companies  is  on  the  same  principle  of  attempting  to  secure  the 

*  Member  Executive  Staff,  Marland  Refining  Co. 

VOL.  Lxv. — 23. 


354  APPRAISAL   OF   OIL   PROPERTIES 

benefit  of  money  expended  by  others  in  testing,  but  most  of  them  remove 
the  obnoxious  holdup  feature  by  contributing  toward  such  testing  by 
others  in  proportion  to  the  benefit  they  themselves  secure. 

Fraudulent  stock  promotion,  as  contrasted  with  lease  speculation,  is 
an  unhealthy  disreputable  growth  and  justifies  mention  only  that 
attention  may  be  called  to  the  burden  it  places  upon  the  oil  industry. 
The  value  of  an  oil  property  for  this  purpose  has  no  real  relation  to  its 
productive  value,  the  property  being  selected  for  its  adaptability  to  a 
fantastic  tale  of  fabulous  earnings  to  draw  money  from  people  with 
small  savings.  Consequently,  the  promoter  pays  for  leases  suitable  to 
his  purpose  prices  entirely  out  of  proportion  to  their  probable  economic 
value.  Such  prices,  however,  immediately  influence  owners  of  surround- 
ing unleased  areas  when  dealing  with  the  legitimate  operator. 

The  lease  speculator  and  fraudulent-stock  promoter,  while  entirely 
dissimilar  in  their  standards  of  ethics  and  respectability,  have,  therefore, 
this  in  common — they  tend  to  place  on  prospective  oil-producing  areas, 
before  these  get  into  the  hands  of  the  oil  operator,  values  that  have  little 
relation  to  their  economic  value.  The  impossibility  of  determining  the 
exact  economic  value,  the  knowledge  that  other  men  are  paying  like  prices, 
and  the  optimistic  spirit  of  the  operator  generally  lead  him  to  meet 
these  fictitious  values  and  pay  prices  for  undeveloped  leases,  especially 
in  the  vicinity  of  a  new  discovery,  entirely  out  of  proportion  to  their 
chances  of  being  profitably  productive. 

Prior  to  1888,  the  American  oil  industry  was  operated  in  two  distinct 
divisions :  first,  that  of  the  producer,  who  brought  the  oil  to  the  surface ; 
and,  second,  that  of  the  refiner,  who  purchased  the  crude  oil  at  the  well 
and  carried  it  through  all  remaining  phases,  including,  in  some  instances, 
its  sale  to  the  consumer.  However,  about  the  date  mentioned,  would-be 
competitors  of  the  then  dominant  refining  interest,  recognizing  the  neces- 
sity of  owning  and  controlling  producing  properties  as  an  insurance 
against  disturbance  of  their  crude  supply,  began  to  acquire  oil-pro- 
ducing properties.  The  dominant  refining  interest  quickly  adopted  the 
same  practice,  until  now  the  greater  percentage  of  production  is  owned 
and  controlled  as  a  necessary  adjunct  to  the  refining  and  transporting 
branches  of  the  industry.  New  pools,  when  opened,  have  diverse  owner- 
ship but  eventually  gravitate,  to  a  great  extent,  into  the  character  of 
control  mentioned.  Thus,  while  to  the  oil  producer,  as  such,  an  oil 
property  has  value  only  to  the  extent  of  the  margin  of  profit  between 
the  cost  of  the  oil  as  produced  and  his  receipts  for  it  as  sold  in  its  crude 
state,  to  the  refiner  and  transporter  it  has  a  double  value — one  of  which 
is  identical  with  that  of  the  producer,  while  the  second  is  that  it  stabilizes 
and  makes  secure  his  more  important  business  of  transporting  and  refin- 
ing, provided  his  producing  properties  are  so  situated  as  to  make  his 


EARL   OLIVER  355 

production  available  for  his  facilities.  The  value  of  the  property  for  the 
latter  purpose  is  frequently  of  much  greater  importance  than  for  the 
former. 

VALUE  OF  OIL  PROPERTY  TO  THE  PRODUCER 

The  value  of  an  oil  property  to  a  producer  as  such  (stripped  of  its 
speculative  feature)  is  simple  in  principle  and  is  nothing  more  nor  less 
than  the  present  worth  of  the  aggregate  margin  of  profit  between  the 
expenditures  for  producing,  saving  and  disposing  of  the  oil  in  its  crude 
state  and  the  price  received  for  the  same.  To  ascertain  such  value  is 
a  simple  matter  in  accounting — of  balancing  expenditures  against  re- 
ceipts and  introducing  interest  charges.  It  differs  little  from  the  average 
bookkeeper's  problems  except  that  it  is  reversed.  The  bookkeeper 
balances  expenditures  against  receipts  on  business  that  is  past;  the  oil- 
property  appraiser  balances  expenditures  against  receipts  on  business  of 
the  future.  To  his  bookkeeping  ability  he  must,  therefore,  add  the 
ability  to  see  into  the  future — and  underground  as  well. 

His  principal  difficulties  are  to  determine  the  number  of  barrels  of 
oil  the  particular  property  will  produce  and  the  price  per  barrel  he  will 
receive.  He  has  several  other  factors  to  consider,  such  as  the  cost  of  de- 
veloping, and  of  maintenance  and  operating,  but  these  are  easily  disposed 
of  if  he  is  able  to  accurately  forecast  the  first  two  named. 

Until  within  very  recent  times  there  has  been  no  one  well-established, 
widely  used,  generally  accepted  method  of  determining  the  probable 
future  production  of  an  oil  property.  Scientists  have  evolved  general 
theories  as  to  the  laws  controlling  the  accumulation  of  petroleum  that 
have  much  merit;  in  a  large  way,  they  are  helpful.  It  must,  however,  be 
confessed  that  in  their  early  application,  or  rather  misapplication,  to 
individual  small  tracts  for  valuation  purposes  the  results  obtained  by  them 
have  been  disappointing.  These  theories  introduce  too  many  assump- 
tions to  make  the  appraisals  safe  as  a  basis  upon  which  to  invest  large 
sums  of  money.  Consequently,  an  experienced  oil  producer,  who  had 
the  details  of  a  few  properties  stored  in  his  mind  for  the  purpose  of  com- 
parison, was  more  successful  in  judging  values  of  oil  properties. 

But  the  average  oil  producer,  whose  real  business  is  operating  the 
properties  he  controls,  has  no  inclination  nor  time  to  collect  data  that 
would  give  him  a  wider  vision  than  his  own  experience  furnishes  him, 
and  is  handicapped  to  that  extent.  These  two  men,  the  scientific  theo- 
rist and  the  experienced  oil  producer,  represent  the  two  types  of  appraisers 
that  have  been  known  to  the  oil  industry  for  many  years.  The  difference 
between  them  might  be  better  understood  by  stating  that  the  early 
petroleum  engineer,  in  purchasing  a  race  horse,  would  have  investigated 
carefully  the  history  of  the  dam  and  sire  for  several  generations  back, 


356  APPRAISAL   OF   OIL   PROPERTIES 

ascertained  what  food  and  treatment  the  dam  had  prior  to  the  foaling, 
would  have  given  a  hasty  glance  at  the  horse  itself  and  concluded,  that 
in  view  of  the  record  of  its  progenitors  and  the  early  influence  brought 
to  bear  upon  it,  it  should  be  able  to  do  a  mile  in  2  min.  flat,  and,  accord- 
ingly, purchase  it  on  that  basis.  Whereas,  the  producer,  purchasing 
the  same  horse,  would  send  it  around  the  track,  time  it,  and  buy  it  on  the 
speed  shown,  in  ignorance  of  inherited  and  prenatal  influences. 

There  is  now  being  evolved  a  new  type  of  petroleum  engineer.  He 
knows  the  theories  of  the  scientist,  but  he  demands  that  they  shall  be 
measured  up  with  actual  results.  He  knows  what  percentage  of  struc- 
tures in  a  given  locality  have  been  found  productive  or  barren  upon  being 
tested.  He  knows,  from  compiled  data,  where  oil  accumulates.  He 
calculates  oil  content  per  acre  by  counting  barrels  actually  produced  from 
similar  areas  already  exhausted.  He  measures  the  numerous  scientific 
theories  with  actual  results.  His  business  is  the  collection  of  complete 
data  from  innumerable  properties  so  that  he  may  know  the  habits  of 
petroleum,  instead  of  assuming  for  it  certain  habits  in  keeping  with  his 
ideas  of  what  they  should  be.  This  new  type  of  petroleum  engineer  is 
expected  to  develop  methods  of  determining  the  probable  productiveness 
of  certain  areas  with  much  greater  accuracy  than  the  methods  now  avail- 
able will  permit.  However,  until  such  methods  and  data  are  available, 
it  is  necessary  to  use  the  older  general  principles. 

METHOD  OF  APPRAISING  OIL  PROPERTY 

The  property  is  first  divided  into  developed  and  undeveloped  por- 
tions. The  developed  portion  is  then  subdivided  into  " settled"  and 
"flush"  productions,  provided  the  old  and  new  wells  are  not  so  inter- 
mingled as  to  make  this  impracticable.  For  both  classes  it  is  desirable 
to  have  production  figures  extending  back  month  by  month  to  the  com- 
pletion of  the  wells.  Should  these  figures  not  be  available,  they  should 
at  least  run  back  one  or  two  years,  if  the  wells  are  old  enough. 
There  will,  of  course,  in  so  far  as  it  is  available,  be  a  complete  history  of 
each  well  and  full  data  regarding  it,  including,  among  other  things,  date 
of  completion,  initial  and  present  productions,  thickness  and  depth  of 
sands,  casing  record,  gas  and  water  production,  vacuum  application, 
etc.  One  purpose  is  to  ascertain  whether  the  composite  production  is 
made  up  of  comparatively  uniform  wells,  and  whether  the  production 
figures  as  shown  month  by  month  represent  the  regular  and  natural  rate 
of  decline,  or  whether  some  unusual  condition  might  have  changed  the 
past  production  from  the  natural  rate.  Should  there  be  such  condition, 
its  influence  is  given  such  consideration  as  it  appears  to  warrant,  and  it  is 
eliminated,  if  possible,  from  the  figures. 

On  the  "settled"  production  figures,  a  curve  is  then  constructed 
covering  the  entire  past  life  of  the  property  in  so  far  as  such  figures  are 


EARL   OLIVER  357 

available.  While  properties  of  the  same  age  differ  greatly  in  their  rates 
of  decline,  each  property,  throughout  its  entire  history,  is  characterized 
by  the  same  rate  of  decline;  i.e.,  if  during  the  first  part  of  its  history  it 
shows  a  rapid  rate  as  compared  with  other  properties  of  like  production 
per  well  and  age,  it  will  have  a  rapid  rate  up  to  the  point  of  exhaustion. 
After  the  flush  production  is  off,  provided  the  wells  are  not  unusually 
large,  the  rate  of  decline  is  so  uniform  as  to  make  possible,  for  all  practical 
purposes,  the  use  of  some  definite  percentage  each  year  from  the  previous 
year.  Thus,  some  properties  will  decline  at  the  average  rate  of  40  per 
cent,  each  year  from  the  previous  year,  while  other  properties  will  de- 
cline only  at  the  average  rate  of  15  per  cent.  Consequently,  when  on 
settled  production  the  figures  are  available,  by  constructing  a  curve 
running  back  several  years,  it  is  comparatively  easy  and  safe  to  project 
the  curve  to  the  point  of  exhaustion.  Of  course,  it  must  be  seen  that 
some  extraneous  influence  does  not  cause  the  decline  to  deviate  from  its 
natural  rate. 

For  the  appraisal  of  individual  settled  properties,  where  something 
more  reliable  than  mere  generalities  is  desired,  a  general  production 
curve  should  not  be  used;  instead  the  curve  of  the  property  itself 
should  be  projected.  The  writer  has  before  him  curves  of  several 
Bartlesville  sand  properties  6  to  8  years  old  in  substantially  the  same 
district,  and  which  would  ordinarily  be  considered  of  the  same  type  and 
subject  to  the  same  decline  curve.  Yet  they  range  from  15  per  cent, 
annual  decline  on  some  properties  to  40  per  cent,  on  others,  which  means 
that  the  first  named,  although  having  no  more  present  daily  production 
than  the  latter,  will  produce  three  times  as  much  as  the  latter  before 
exhaustion. 

Every  producing  property  is  a  type  unto  itself  and  where  reliable  ap- 
praisal is  desired  no  property  can  be  thrown  into  any  general  class  at  so 
much  per  barrel.  Each  property  has  characteristics  that  place  it  above  or 
below  the  average  and  as  stated  on  settled  production,  located  apart 
from  new  wells,  it  is  desirable  that  its  own  production  curve  be  projected. 

With  flush  production,  however,  this  cannot  be  done  since  there  will 
not  have  elapsed  sufficient  time  to  indicate  a  rate  of  decline.  Reliance 
upon  general  decline  curves  cannot  be  avoided,  but  care  should  be 
taken  to  select  a  curve  compiled  from  properties  as  similar  in  type 
as  it  is  possible  to  secure.  As  a  check,  data  compiled  from  similar  prop- 
erties as  to  yield  per  acre-foot  is  helpful  for  "  flush  productions,"  although 
of  too  general  nature  to  be  of  assistance  in  appraising  "settled"  produc- 
tion. Briefly,  therefore,  for  "settled"  production  the  curve  of  the  prop- 
erty examined  should  be  projected  while  for  "flush"  production  the  use 
of  a  general  decline  curve  compiled  from  similar  properties  is  permissible. 

The  undeveloped  portion  of  a  property  should  be  viewed  from  an 
entirely  different  angle.  This  will  range  from  so-called  rank  "wildcat" 


358  APPRAISAL   OF   OIL   PROPERTIES 

acreage  up  to  that  which  is  sufficiently  surrounded  by  production  as  to 
be  substantially  proved.  It  is  rare,  however,  that  any  undrilled  acreage 
will  be  so  thoroughly  proved  as  to  justify  a  method  of  appraisal  that 
will  include  assumption  of  a  certain  number  of  locations  with  an  assumed 
initial  production  per  well  and  with  application  thereto  of  a  decline  curve. 
Theoretically  such  method  appears  satisfactory  but  it  does  not  work  out 
well  in  practice.  However  conservative  the  appraiser  attempts  to  be 
such  method  of  appraising  generally  leads  to  overvaluation.  It  is  poor 
practice.  Such  a  method  starts  with  the  assumption  that  the  undrilled 
acreage  will  be  productive  and  then  attempts  to  call  to  mind  all  factors 
of  uncertainty  for  which  discount  should  be  made  but  some  of  these  will 
be  missed  and  the  property  be,  thereby,  given  a  higher  rating  as  to  cer- 
tainty of  production  than,  as  a  rule,  it  justifies. 

The  basic  assumption  on  undrilled  acreage  should  be  the  reverse  of 
the  above;  i.e.,  that  it  is  barren,  and  then  such  factors  should  be  assembled 
as  will  tend  to  take  it  out  of  that  class.  Perhaps  this  distinction  has  not 
been  made  clear  and  it  has  reference  only  to  the  state  of  mind  of  the 
appraiser  toward  the  property,  but  this  tendency  toward  optimism  re- 
garding the  probable  productiveness  of  acreage  has  caused  much  more 
money  to  be  spent  in  the  attempt  to  produce  oil  than  the  industry  has 
paid  back  in  the  aggregate  to  the  producer.  By  the  very  nature  of  the 
industry  there  must  be  great  individual  gains  and  losses  but  the  industry 
as  a  whole  should  pay  its  own  way;  and  the  fact  that  it  does  not  in  the 
aggregate  do  so  should  be  more  widely  recognized  and  values  adjusted 
accordingly. 

It  is  in  this  field  of  undeveloped  acreage  that  the  work  of  the  petrol- 
eum engineer  is  in  most  need  of  extension.  Comprehensive  data  showing 
the  percentage  of  seemingly  favorable  structure  that  has  proved  profitably 
productive,  the  conformity  of  subsurface  to  surface  structure  in  given 
districts,  the  percentage  of  production  seemingly  off  structure,  the  per- 
sistence of  sands,  the  yield  per  acre-foot,  and  thorough  study  of  the 
accumulation  of  oil  as  it  is  actually  found  to  exist  rather  than  a  preconceived 
theory  of  how  it  should  accumulate,  together  with  a  more  widely  spread 
knowledge  of  the  results  will  be  helpful  to  the  industry  and  place  unde- 
veloped acreage  on  a  proper  footing.  Such  factors  together  with  many 
others  must  be  taken  into  consideration  by  him  who  would  appraise 
undeveloped  acreage  with  any  degree  of  safety.  This  investigation  must, 
however,  be  made  with  the  cold  calculating  analysis  of  the  engineer — 
who  looks  only  at  facts,  rather  than  by  the  scientist  whose  province  is 
farther  afield. 

A  factor  in  the  appraisal  of  oil  properties  of  almost  equal  importance 
to  the  amount  of  oil  secured  is  the  price  to  be  received  for  the  oil.  Re- 
gardless of  the  views  sometimes  asserted,  the  market  price  of  crude  oil 
and  the  usual  fluctuations  are  influenced  by  the  law  of  supply  and 


EARL   OLIVER  359 

demand.  In  attempting  to  forecast  the  price  that  might  reasonably 
be  expected  for  the  oil  output  of  a  property  it  is,  therefore,  necessary  to 
assemble  and  consider  the  factors  that  will  influence  supply  and  demand. 
This  is  a  large  field;  there  is  no  intention  to  say  that  an  actual  price  can 
be  forecast,  but  that  the  market  trend  can  be  reasonably  foreseen  over 
at  least  the  next  thereafter  succeeding  2  or  3  years.  However,  this 
phase  of  the  subject  must  be  left  for  future  discussion. 

Having  determined  upon  extent  and  rate  of  production  that  might 
reasonably  be  expected  from  a  property  and  the  probable  trend  of  the 
market  price,  there  then  enter  the  cost  of  development  and  maintenance 
and  the  consideration  that  should  be  given  the  possibility  of  increasing 
the  amount  of  oil  to  be  produced  by  the  application  of  different  methods. 
This,  again,  is  an  uncertain  field  and  if  the  property  is  fully  drilled  such 
possibility  frequently  no  more  than  offsets  the  dangers  unseen.  The 
equipment  that  is  needed  for  the  permanent  operation  of  the  property 
should  be  given  no  credit  unless  the  property  is  relatively  near  the  point 
of  abandonment. 


FACTORS  INFLUENCING  VALUATION  OF  OIL  PROPERTY 

A  few  of  the  questions  that  must  be  considered  by  one  who  would 
eliminate  as  much  as  possible  the  factors  of  uncertainty  in  the  purchase 
of  properties,  together  with  the  character  of  information  that  would  be 
helpful  are  here  given,  although  the  outline  is  by  no  means  complete. 

I.  Plans  of  Purchaser 

1.  General  scope  and  business  of  company 

2.  Purpose  for  which  property  is  needed 

3.  Amount  of  oil  needed 

4.  Amount  of  money  available  to  secure  it 

II.  Probable  Oil  Market  Trend 

1.  Production:  (a)  World's  past  and  present  production,  in  detail  by  coun- 

tries and  districts,  and  by  whom  controlled,  in  each  instance  giving 
wells  completed  and  producing.  (6)  World's  probable  future  production 
by  countries  and  districts,  and  by  whom  controlled. 

2.  Consumption:  (a)  World's  past  and  present  consumption,  showing  dis- 

tribution by  countries  and  districts  and  distribution  as  to  use.  (6)  The 
world's  probable  future  needs  as  to  countries  and  as  to  uses. 

3.  Prices:  (a)  Of  crude  oil.     (6)  Of  refined  products,     (c)  Margin  of  profits. 

(d)  Prices  to  which  crude  petroleum  might  go  before  other  products  be- 
come competitor. 

4.  Graphic  charts  of  prices,  production,  and  consumption 

5.  Possible  substitutes  and  probable  influence  of  same 

6.  General  consideration  of  factors  that  might  influence  price,  and  survey  of 

the  entire  field  of  market  trend 


360  APPRAISAL  OF  OIL  PROPERTIES 

III.  Selection  of  Regions  for  Exploitation 

1.  Geographical  location 

2.  Geology:   (a)  General  petroleum  possibilities.     (6)  Laws  controlling  local 

accumulations,  (c)  Degree  of  conformity  of  production  to  structure. 
(d)  Persistency,  thickness,  and  characteristics  of  petroleum-producing 
strata,  (e)  Comprehensive  data  showing  actual  petroleum  extracted 
per  acre-foot  from  all  types  of  producing  strata.  (/)  Rate  of  decline  of 
various  types  of  producing  properties,  with  described  conditions,  (g) 
Water  conditions. 

3.  Development:  (a)  Past  history.     (6)  Maps  marked  up  to  date. 

4.  Oil:  (a)  Quality,     (b)  Amount  produced  by  periods,     (c)  Market  price  of 

same  by  periods,     (d)  To  whom  sold. 

5.  Relative  cost  to  operate:   (a)  Depth  and  cost  of  wells.     (6)  Method  of 

operation,     (c)  Proximity  to  supplies  and  markets. 

6.  Relation  to  transportation  systems 

7.  Relation  to  company's  plans  and  its  existing  properties 

8.  Ownership  compilations:  (a)  Production  figures  and  comprehensive  owner- 

ship data  on  producing  properties.  (6)  Comprehensive  ownership  data 
on  non-producing  lands. 

9.  Records  of  sales  of  both  producing  and  non-producing  properties  to  indi- 
cate prevailing  prices 

IV.  Selection  of  Properties.    This  section  deals  with  especially  selected  properties 
that  might  be  worthy  of  consideration  as  contrasted  with  regions  dealt  with  in 
section  III  and  therefore  goes  much  more  into  detail  in  each  case. 

1.  Geographical  and  legal  description 

2.  Geology:  (a)  Surface,     (b)  Underground,     (c)  Persistence,  thickness  and 

characteristics  of  possible  producing  strata,  (d)  Water  conditions,  (e) 
Application  to  this  property  of  laws  of  accumulation  peculiar  to  region. 
(/)  Data  showing  production  per  acre-foot  from  similar  already 
exhausted  properties,  (g)  Data  showing  probable  rate  of  decline  de- 
duced from  past  history  of  this  property,  also  from  similar  already 
exhausted  properties. 

3.  Development:   (a)  History.     (6)  Well  records,     (c)  Maps  marked  up  to 

date,  including  adjoining  properties. 

4.  Oil:   (a)   Quality.     (6)   Amount  by  periods  produced  from  beginning  of 

development,  (c)  Market  price,  (d)  Possible  markets,  (e)  Probable 
amount  to  be  produced,  (f)  Probable  rate  of  decline. 

5.  Relative  cost  to  operate:  (a)  Depth  and  cost  of  wells,     (b)  Production 

expense,  (c)  Method  of  operation,  (d)  Equipment,  (e)  Proximity  to 
supplies,  labor,  and  markets. 

6.  Relation  to  transportation  systems 

7.  Relation  to  company's  plans  and  its  existing  properties 

8.  Records  of  sales  of  similar  properties  to  indicate  prevailing  prices 

V.  Terms  of  Lease 

1.  Rate  of  royalty  3.  Development  requirements 

2.  Term  to  run  4.  Unusual  conditions 

VI.  Taxation  questions  and  general  governmental  conditions  and  safeguards 
VII.  Conditions  of  title 


DISCUSSION  361 

DISCUSSION 

CARL  H.  BEAL,  San  Francisco  (written  discussion). — I  heartily 
endorse  the  statement  that  the  petroleum  engineer  should  look  at  oil 
properties,  if  possible,  from  the  viewpoint  of  the  practical  operator. 
Too  much  appraising  has  been  based  on  theory  and  not  enough  on  facts. 
If  the  facts  were  not  available,  this  process  of  appraising  might  be  con- 
doned; but  the  files  of  practically  every  oil  company  contain  consider- 
able data  of  importance  that  should  be  studied  in  connection  with  oil 
production. 

Mr.  Oliver  has  brought  out  one  important  fact;  that  is,  the  influence 
of  the  speculator  and  the  fraudulent  stock  promoter  on  the  selling  price 
of  leases.  These  men  greatly  increase  the  amounts  that  must  be  paid 
for  proved  and  wildcat  land.  Incidentally,  this  fact  makes  difficult  the 
adoption,  by  the  Treasury  Department,  of  sales  values  of  actual  trans- 
actions as  a  method  of  limiting  the  values  placed  on  developed  and  partly 
developed  oil  land.  Some  time  ago  this  method  was  suggested  as  one 
that  would  be  used  as  a  possible  limitation  by  the  Department  in  check- 
ing valuations  made  for  the  purpose  of  determining  the  depletion  deduc- 
tion. High  market  values  nearly  always  prevail  in  a  new  field  where  the 
excitement  is  running  high.  Ranger  a  year  ago  is  a  good  example.  The 
actual  amounts  of  oil  that  could  be  obtained  from  some  of  the  partly 
developed  leases  would  lack  much  of  measuring  up  to  the  average  sales 
values  of  surrounding  properties.  Market  values  much  higher  than 
intrinsic  values  indicate  a  speculative  period,  whereas  intrinsic  values  in 
excess  of  market  values  indicate  a  period  of  stagnation,  when  oil-property 
transactions  are  rare.  The  market  values  may  fluctuate  rapidly  because 
of  new  discoveries,  but  the  actual  value  reposing  in  the  oil  does  not 
change,  except  as  the  factors  influencing  such  values  change;  for  instance, 
an  increased  demand,  lower  or  higher  drilling  costs,  etc.  An  average  of 
exchange  values  over  a  long  period  of  years  would  equal  the  actual  value 
of  the  properties,  for  the  prices  paid  during  periods  of  excitement  and 
periods  of  depression  will  result  in  an  average  that  fairly  represents 
actual  value. 

Mr.  Oliver  separates  the  developed  from  the  undeveloped  parts  of  the 
property  and  then  the  "settled"  from  the  " flush"  production.  It  often 
has  been  very  difficult  for  me  to  separate  the  flush  and  settled  pro- 
ductions, for  there  seems  to  be  no  particular  line  of  separation  between 
them.  In  some  places  the  wells  may  be  called  settled  after  6  months,  in 
others  after  1  year,  whereas  other  wells  may  be  called  settled  from  the 
very  beginning.  The  age  of  a  well  when  its  production  is  settled  varies 
with  the  initial  production  and  the  conditions  under  which  the  oil  is 
produced.  A  well  drilled  in  the  Lima-Indiana  field  coming  in  at  10  or 
15  bbl.  a  day  very  likely  will  have  but  a  short  period  of  flush  production; 


362  APPRAISAL   OP   OIL   PROPERTIES 

whereas  a  5000-bbl.  well  in  California  may  be  irregular  in  its  production 
for  several  months,  or  even  2  or  3  years.  Flush  production  is  a  relative 
term — of  use  in  describing  production  of  individual  properties,  but  diffi- 
cult to  define. 

The  future  production  of  wells  still  in  their  youth  may  be  estimated 
from  data  showing  the  relation  of  the  production  of  a  well  the  first  day 
or  month  to  its  output  during  the  first  year.  Most  production  curves 
used  in  estimating  the  future  production  of  oil  properties  are  based  on 
the  rate  of  decline  of  wells,  which  produce  different  amounts  the  first 
year.  If  the  relationship  between  the  production  of  the  first  day  or  the 
first  month  and  the  production  of  the  first  year  can  be  determined,  the 
estimate  of  the  future  production  of  new  wells  may  be  much  more  accu- 
rately made  than  by  the  method  suggested  by  Mr.  Oliver.  I  found  by 
studying  many  records  in  Oklahoma  that  the  average  well  in  the  fields 
east  of  Gushing  would  produce  daily,  in  the  first  year,  about  25  per  cent, 
of  its  initial  daily  production.  In  other  words,  if  the  initial  production  of 
a  well  were  100  bbl.,  its  first  year's  production  would  be  about  9000  bbl.; 
although  this  ratio  changes  for  wells  of  different  initial  output,  it  may 
be  used  in  roughly  estimating  the  amount  a  new  well  would  make  the 
first  year.  In  California,  I  find  this  ratio  to  be  much  different;  for 
instance,  in  some  fields  a  100-bbl.  well  will  make  between  50  and  75  bbl. 
daily  the  first  year. 

The  statement  that  where  individual  properties  are  being  appraised 
a  curve  of  the  property  itself  should  be  projected,  for  estimating  the  future 
production  of  that  property,  cannot  be  too  strongly  emphasized.  Some 
of  us  are  prone  to  apply  average  curves,  but  the  curves  of  the  property 
itself  are  very  much  more  trustworthy  and  simpler  to  use.  The  details 
of  preparing  such  a  curve  are  simple.  The  annual  production  should  be 
obtained,  if  possible,  for  the  life  of  the  property,  and  the  average  number 
of  wells  producing  divided  into  this  annual  production.  The  result- 
ing amounts  are  the  annual  production  per  well  of  the  property.  In 
almost  any  property  where  drilling  has  been  carried  on  at  a  normal  rate 
the  peak  of  production  of  the  property  will  occur  only  a  few  years  after 
the  first  well  has  been  drilled;  often  it  will  occur  in  the  first  or  second  year. 
From  that  time  on,  regardless  of  the  rate  at  which  the  property  is  drilled, 
the  annual  production  per  well  decreases.  This  curve,  projected  into  the 
future,  will  show  the  estimated  annual  production  per  well.  The  only 
remaining  step  in  the  problem  is  to  estimate  the  number  of  wells  that  will 
be  producing  each  year  in  the  future.  After  these  annual  amounts  have 
been  determined,  they  are  multiplied  by  the  estimated  annual  production 
per  well;  the  product  is  the  estimated  future  annual  production. 

Possibly  one  reason  that  this  method  has  not  been  used  more  is 
because  some  persons  believe  that,  as  all  wells  in  the  field  have  not  been 
drilled,  the  daily  production  per  well  will  be  upheld  by  the  yield  of  new 


DISCUSSION  363 

wells.  This  objection  is  not  valid,  especially  if  the  production  per  well 
in  the  district  has  begun  to  decline  on  account  of  interference.  After  a 
field  or  property  has  attained  a  certain  age,  the  decline  in  the  daily  pro- 
duction per  well  remains  practically  unchanged,  regardless  of  the  number 
of  new  wells  drilled.  It  is  necessary,  however,  that  the  wells  shall  be 
drilled  close  enough  to  be  affected  by  drainage.  In  a  field  where  the  pro- 
ductive sand  is  lenticular,  or  made  up  of  several  disconnected  lenses,  or 
if  the  wells  are  widely  spaced,  this  method  cannot  always  be  used. 

Referring  to  Mr.  Oliver's  statement  that  yield  per  acre -foot  should 
be  obtained,  I  have  not  been  able  to  obtain  sufficient  data  to  prove 
that  such  statistics  are  of  any  value.  Production  per  acre,  I  believe, 
is  very  much  preferred,  for  the  reason  that  it  is  practically  impossible 
for  anyone  to  determine  the  portion  of  a  sand  that  produces  the 
oil.  The  thickness  is  not  measured  accurately  in  the  first  place.  Some 
parts  of  the  sand  are  more  porous  than  others,  and  some  parts  produce 
water.  It  is  possible  that  the  pressures  in  the  various  members  of  an  oil 
sand  or  zone  may  be  different.  The  first  production  of  a  well  may  come 
from  two-thirds  of  the  sand,  until  the  pressure  is  reduced  to  that  of  other 
members  of  the  sand,  and  the  next  portion  of  the  production  may  be 
expelled  from  all  parts  of  the  sand.  Statistics  on  production  per  acre 
from  a  sand  like  the  Bradford  sand  in  northwestern  Pennsylvania  prob- 
ably would  be  of  some  value,  but  most  of  the  oil  sands  with  which  I  am 
acquainted  are  so  irregular  that  statistics  of  production  per  acre-foot 
cannot  be  compiled  that  are  of  any  particular  use. 

The  reference  to  the  necessity  of  estimating  future  price  of  oil  in 
oil-land  appraisals  brings  up  one  of  the  most  difficult  factors  in  valuations. 
Although,  as  Mr.  Oliver  says,the  market  trend  can  be  reasonably  fore- 
seen over  at  least  the  next  2  or  3  years,  to  forecast  future  price  for  several 
years,  as  is  necessary  in  oil-land  appraisals,  is  not  in  accordance  with  the 
exactitude  that  engineers  desire  in  their  profession.  The  fact  remains, 
however,  that  some  estimate  must  be  made,  and  the  engineer  is  the  man 
who  must  make  it.  In  making  the  estimate,  it  is  necessary  for  him  to 
consider  the  economic  side  of  the  oil  industry;  a  small  variation  in  the 
price  of  oil  may  mean  the  difference  between  gain  or  loss.  In  fact, 
since  the  working  out  of  new  and  more  trustworthy  methods  for  more 
accurately  estimating  future  oil  production,  the  estimation  of  the  future 
price  has  become  one  of  the  most  uncertain  elements  to  be  contended  with. 

R.  H.  JOHNSON,  Pittsburgh,  Pa. — Stress  on  division  of  the  flush 
and  settled  periods  is  an  unfortunate  habit.  It  is  far  better  for  us 
to  think  of  the  thing  as  a  curve  than  to  get  this  other  impression. 
Mr.  Oliver  takes  a  regular  percentage  decline  for  several  years  after 
he  says  the  well  is  settled;  in  the  flush  period  we  are  not  offered  any 
particular  guidance.  That  is  unfortunate.  It  is  in  the  flush  period 


364  APPRAISAL   OF   OIL  PROPERTIES 

that  a  great  many  purchases  are  made;  and  the  man  who  is  trying  to 
find  out  the  values  of  properties,  the  man  who  wishes  the  services  of  the 
appraiser,  is  very  much  concerned  with  that  period.  If  we  think 
of  this  whole  thing  as  a  curve  and  study  the  problem  as  a  whole,  we  are 
on  a  more  healthful  basis  than  this  artificial  distinction. 

Mr.  Oliver  has  exaggerated  the  period  of  time  that  one  is  safe  in  using 
the  same  percentage  of  decline  year  to  year.  It  is  true  that  we  approach 
such  a  curve  in  the  old  age  of  the  well,  but  Mr.  Oliver  starts  too  early 
to  assume  that  we  can  take  a  constant  percentage  of  decline. 

Mr.  Oliver  should  have  given  some  attention  to  the  compound 
discount  factor  in  working  out  present  worths.  He  says  that  the  prices, 
in  the  long  run  of  exchange  values,  will  average  the  productive  value,  that 
is,  the  periods  of  inflation  will  cancel  the  periods  of  depreciation,  so  that 
in  the  long  run  productive  values  must  be  the  same  as  exchange  values. 
This  is  not  correct.  Except  in  periods  of  excitement,  we  generally  make 
a  considerable  allowance  for  risk.  I  never  like  to  recommend  the  pur- 
chase of  a  property  at  exactly  what  I  think  it  is  worth.  I  always  feel  that 
we  should  recommend  a  liberal  allowance  for  risk  to  a  purchaser.  To 
be  sure,  there  are  inflated  values,  but  they  are  recognizable.  In  fact,  it 
is  not  uncommon  to  find  old  operators  who  say  that  they  buy  on  the 
basis  of  paying  out  in  four,  or  some  other  number  of  years.  To  be  sure, 
these  men  have  not  made  a  regular  allowance  for  compound  discount. 
It  is  probably  partly  involved  in  this  expression  of  theirs,  although 
they  do  not  realize  it,  but  it  is  also  partly  the  fact  that  they  wish  to 
allow  an  ample  amount  for  risk.  That  should  be  the  custom  of  all 
buyers,  with  the  possible  exception  of  the  one  who  has  a  large  refinery 
that  must  be  kept  going  and  who  must  protect  himself  from  loss  at  other 
points. 


VARIATION   IN   DECLINE   OP  VARIOUS   OIL   POOLS 


365 


Variation  in  Decline  Curves  of  Various  Oil  Pools 

BY  R  os WELL  H.  JOHNSON,  M.  S.,  PITTSBURGH,  PA. 

(New  York  Meeting,  February,  1920) 

THE  Manual  of  the  Oil  and  Gas  Industry,  under  the  Revenue  Act  of 
1918,  published  by  the  Treasury  Department  for  the  guidance  of  oil 
companies  in  preparing  their  estimates  of  future  recoverable  oil  for  the 
purpose  of  calculating  depletion,  gives  the  first  large  public  collection  of 
comparative  decline  curves  for  the  whole  country.  It  is  a  matter  of  both 
scientific  and  practical  interest  to  so  arrange  these  data  that  the  pools  can 
be  readily  compared.  There  are  certain  difficulties  in  such  a  comparison, 
however:  (1)  The  economic  limit  varies  from  50  to  2000  bbl.  a  year  in 
different  pools  taken.  (2)  Because  of  this  variation  in  economic  limit, 
the  range  of  data  shown  makes  comparison  possible  only  for  wells  of 
intermediate  size. 

In  order  to  be  as  inclusive  as  possible,  I  have  taken  as  an  expression 
of  the  rate  of  decline  the  amount  of  oil  produced  in  the  period  during 
which  a  well  drops  from  3000  to  2000  bbl.  a  year.  No  period  of 
smaller  production  could  be  used  because  of  the  high  economic  limit  in 
California;  and  no  period  of  larger  production  and  yet  include  the  small 
well  areas  of  the  Appalachian.  As  it  is,  the  Lima-Indiana  wells  are 
excluded.  In  a  few  instances,  curves  were  extrapolated  to  obtain  the 
reading,  where  the  curve  seemed  regular  enough  to  warrant  it. 

In  general,  the  amount  of  oil,  in  barrels,  produced  while  a  well  de- 
clined from  3000  bbl.  to  2000  bbl.  a  year  is  shown  in  Table  1. 


TABLE  1.— Production  of  Wells  During  Decline  from  3000  to  2000 

Barrels  a  Year 


Field 

Minimum 
Barrels 

Median 
Barrels 

Mean 
Barrels 

Maximum 
Barrels 

California  

2,500 

5,800 

6,260 

10,200 

Gulf  Coast  (Saratoga  only) 

2,160 

3930 

5700 

South  Mid-Continent  

1,700 

2,700 

2,666 

3,600 

Gulf  Cretaceous  

1,000 

1,500 

2,175 

5600 

Mid-Continent  .  .  . 

600 

1  350 

1  785 

3400 

Rocky  Mountains  

700 

1,310 

3,170 

7,500 

Appalachian  

450 

1,225 

1,489 

2.750 

Illinois  

410 

1  288 

1  285 

2200 

366  VARIATION   IN   DECLINE   OF  VARIOUS   OIL   POOLS 

Amount  of  oil  produced  while  well  declined  from  3000  to  2000  bbl.  a  year. 

Appalachian  Field 

BARRELS 

Big  Injun  sand,  Roane  Co.,  W.  Va 2550 

Gordon  sand,  Greene  Co.,  Pa ' 2300 

Berea  sand,  Lincoln  Co.,  W.  Va 1900 

Gordon  sand,  Wetzel  Co.,  W.  Va 1850 

Shinnston  pool,  Harrison  Co.,  W.  Va 1400 

Clinton  sand,  Wayne  and  Hocking  Co.,  Ohio 1300 

Wayne  Co.,  Ky 1150 

Gore  pool,  Perry  and  Hocking  Co.,  Ohio 1050 

St.  Mary's  pool,  Washington  Co.,  Ohio 850 

Dorseyville,  Allegheny  Co.,  Pa 500 

Ragland,  Ky 500 

Irvine,  Ky 450 


Illinois  Field 

BARRELS 

Dennison  pool,  Lawrence  Co.,  Ill 2200 

Siggins  pool,  Cumberland  Co.,  Ill 2075 

Robinson  pool,  Crawford  Co.,  Ill 1550* 

Carlyle  &  Sandoval  pools,  Clinton  and  Marion  Co.,  111. . .  1500* 

Upper  Lawrence  Co.,  Ill 1500 

Birds-Flatrock  pool,  Crawford  Co.,  Ill 1425* 

Pike  Co.,  Ind 1150 

Kirkwood  pool,  Lawrence  Co.,  Ill 1150 

Johnson  pool,  Clark  Co.,  HI 1140* 

Sullivan  pool,  Sullivan  Co.,  Ind 700 

Plymouth  pool,  McDonough  Co.,  Ill 630 

Westfield  pool,  Clark  Co.,  Ill 410* 

*  Extrapolated. 


Oklahoma-Kansas  Field 

BARRELS 

Bird  Creek-Skiatook  district,  Okla 3400 

Glenn  pool,  Okla 3200 

Okesa  district,  Okla 2850 

Avant-Ramona  district,  Okla 2850 

Cleveland  district,  Okla 2800 

Bartlesville-Dewey  district,  Okla 2000 

Okmulgee  district,  Okla 1800 

Blackwell  district,  Okla 1500 

Muskogee-Boynton  district,  Okla Ti<v  •  1350 

Eldorado  district,  Kans.. .V  -  1300 

Augusta  district,  Kans 1200 

Gushing  district,  Okla 1110 

Nowata  district,  Okla -•  1100 

Garber  pool,  Okla 1100 

Adair  district,  Okla 1000 

Neodesha  district,  Kans 600 


ROSWELL   H.    JOHNSON 


367 


South  Mid-Continent  Field 

BARRELS 

Burkburnett  pool 3,600 

Electra  district 2,700 

Healdton  pool 1,700 

Gulf  Cretaceous  Field 

Corsicana  pool 5,600 

Mooringsport  pool 2, 100 

Marion  Co.,  Tex 1,600 

DeSota  parish,  La 1,400 

Vivian  pool,  La 1,350 

Red  River  district,  La 1,000 

Wyoming  Field 

Salt  Creek  pool 7,500 

Grass  Creek  pool 1,310 

Elk  Basin  pool 700 


California  Field 

BARRELS 

Kern  River  pool 10,200 

McKittrick  district. 10,000 

Olinda  district 10,000 

Old  Santa  Maria  pool 9,500 

Fullerton-La  Harba  pool 9,000 

Twenty  Five  Hill  pool 9,300 

Maricopa  Flat  pool 6,700 

West  Side  Coalinga  pool 6,000 

Salt  Lake  pool 5,800 

East  Side  Coalinga  pool 5,500 

Belridge  pool fc 4,500 

Lost  Hills  pool 4,000 

Buena  Vista  Hills  pool 4,000 

Whittier  district 3,900 

West  Coyote  pool 3,500 

Fellows-Midway  district 3,000 

Shields  Canyon  district,  Ventura 

Co 2,500 


The  Gulf  Coast  data  are  given  with  two  different  bases  of  reference, 
so  that  all  the  districts  are  not  mutually  comparable.  Those  under 
each  head  may,  however,  be  compared.  Amount  of  oil  produced  while 
well  declined  from  3000  to  2000  bbl.  a  year:  Saratoga  Rio  Bravo 
normal  spacing,  5700  bbl.;  Saratoga  town  lot  spacing,  2160  bbl. 
Amount  of  oil  produced  while  well  declined  from  500  to  300  bbl.  a 
month : 


BARRELS 

Batson 4780  Humble 

Evangeline 4230  Vinton 

Sour  Lake . .  3075  Goose  Creek . 


BARRELS 
1680 
1530 
1230 


For  the  sake  of  finding  how  the  Lima-Indiana  pool  ranks  with  other 
small-well  pools,  Table  2,  based  on  the  oil  produced  while  the  wells 
are  declining  from  500  to  100  bbl.  a  year,  was  prepared. 


TABLE  2. — Production  of  Wells  During  Decline  from  500  to  100  Barrels 

a  Year 


Field 

Minimum 
Barrels 

Median 
Barrels 

Mean 
Barrels 

Maximum 
Barrels 

Appalachian  .  . 

450 

1700 

1655 

3150 

Limfl.-TndiaTia  . 

965 

1278 

1315 

1990 

Illinois 

400 

1255 

1171 

2100 

368  VARIATION  IN  DECLINE   OF  VARIOUS   OIL   POOLS 

Amount  of  oil  produced  while  well  declined  from  500  to  100  bbl.  a 
year  in  the  various  pools  is  as  follows: 

Appalachian  Pool 

BABBELB 

Fifth  sand,  Pa 3150 

Keener  sand,  Jasper  Ridge  pool,  Monroe  Co.,  Ohio 2850 

Speechley  sand,  Pa 2800 

Bradford  sand,  Pa * 2550 

Floyd  County,  Ky 2050 

Ragland,  Ky 2000 

Gordon  sand,  Allegheny  Co.,  Pa 2000 

Berea  sand,  Lincoln  Co.,  W.  Va '. 1800 

Hundred  foot  sand 1750 

Gordon  sand,  Greene  Co.,  Pa 1700 

Gordon  sand,  Wetzel  Co.,  W.  Va 1700 

Berea  sand,  Jefferson  Co.,  etc.,  Ohio 1600 

Big  Injun  sand 1400 

Keener  sand,  St.  Mary's  pool,  Washington  Co.,  Ohio 1100 

Wayne  Co.,  Ky 850 

Shinnston,  W.  Va 600 

Clinton  sand,  Perry  and  Hocking  Co.,  Ohio 600 

Irvine,  Ky , 600 

Dorseyville,  Pa 450 

Clinton  sand,  Hocking  and  Wayne  Co.,  Ohio 450 

Trenton  Pool 

BARRELS 

Hancock  Co.,  Ohio .  1990 

Wood  Co.,  Ohio 1410 

Seneca  Co.,  Ohio 1380 

Adam  Co.,  Ind 1300 

Ottawa  and  Lima  Co.,  Ohio 1255 

Sandusky  Co.,  Ohio 1230 

Grant  Co.,  Ind 990 

Mercer  Co.,  Ohio 965 

Illinois  Pool 

BARRELS 

Siggins  pool,  111 2100 

Robinson  pool 1850 

Johnson  pool,  111 1780 

Gibson  Co.,  Ind 1425 

Westfield  pool,  111 1270 

Birds-Flatrock  pool 1240 

Pike  Co.,  Ind 835 

Carlyle  and  Sandoval,  111 410 

Plymouth  pool,  111 400 

Sullivan  Co.,  Ind 400 

Caution  must  be  used  in  avoiding  conclusions  based  on  differences  not 
clearly  in  excess  of  probable  error,  yet  the  following  conclusions  seem  to 
be  warranted  from  the  differences  which  are  large  and  consistent. 


ROSWELL   H.   JOHNSON  369 

1  The  widespread  impression  of  the  much  greater  persistence  of  the 
California  field  is  fully  borne  out  in  general,  yet  a  considerable  variation 
is  shown. 

2.  The  great  importance  of  the  thickness  of  pay  is  well  borne  out 
by  the  great  contrast,  in  Wyoming,  between  Salt  Creek  on  the  one 
hand  and  Grass  Creek  and  Elk  Basin  on  the  other. 

3.  The  Gulf  Cretaceous  shows  a  great  contrast  between  the  persistent 
Corsicana  and  much  less  persistent  northern  Louisiana  fields. 

4.  The  south  Mid-Continent  field  shows  an  excellent  persistence  at 
Electra,  Burkburnett,  and  Healdton.     The  more  recent  close  drilling  in 
Burkburnett  and  the  inclusion  of  the  Ranger,  Desdemona  and  Caddo, 
Texas,  pools  will  cause  this  field  to  show  less  favorably  in  the  future. 

5.  The  three  fields  of  oldest  geological  age  all  show  poor  persistence. 
The  hypothesis  that  this  is  characteristic  of  fields  older  than  Devonian 
is  proposed.    This  should  be  expected  theoretically,  as  there  should  be 
an  increased  cementation  in  older  beds,  so  that  the  low  pressures  in  old 
wells  become  impotent'  to  expel  oil.    The  fields  in  question  are  the  Lima- 
Indiana  of  Ordovician  age  and  the  Clinton  and  Hoing  sands  (Plymouth 
pool)  of  Silurian  age. 

6.  The  poor  showing  of  the  Appalachian  fields,  which  are  relatively 
younger  (Dorseyville  and  Shinnston),  is  probably  due  to  the  method 
employed,  which  bases  the  future  history  of  all  wells  on  the  performance 
of  the  small  wells  in  the  early  history  of  the  pool.     These  small  wells, 
having  in  general  a  thinner  pay,  have  a  more  rapid  decline  than  the 
typical  wells  after  they  have  reached  the  same  size. 

7.  The  most  interesting  result  is  that  the  Appalachian  is  apparently 
not  more  persistent  than  the  Mid-Continent,  as  had  been  supposed,  when 
wells  of  the  same  size  are  compared.     The  long  life  of  the  Appalachian 
wells  is  mainly  the  result  of  the  lower  economic  limit.    The  Mid-Continent 
wells  will  show  a  longer  life  as  the  price  in  that  field  rises  and  so  puts 
down  the  "  economic  limit "  of  the  wells.    This  consideration  is  af  avorable 
one  in  the  appraisal  of  Mid-Continent  properties. 

8.  There  is  a  great  variation  from  pool  to  pool  within  the  field.     It 
follows  that  the  attempt  to  appraise  a  property  by  applying  to  it  the 
barrel-day  price  of  a  property  in  some  other  pool  or  sand  or  an  aver- 
age from  many  pools  or  sands  is  unwarranted  where  the  data  permit 
an  analytical  appraisal. 

9.  Since  the  rate  of  decline  is  not  constant,  the  barrel-day  price 
unit  changes  during  the  life  of  a  property,  therefore  barrel-day  prices 
are  not  comparable  except  for  properties  of  similar  age  and  size  as  well 
as  the  same  pool. 


VOL.  LXV. 24. 


370  VARIATION  IN   DECLINE   OF  VARIOUS   OIL   POOLS 

DISCUSSION 

M.  L.  REQUA,  New  York,  N.  Y.  (written  discussion). — In  paragraph 
7  of  his  conclusions,  the  author  states  a  fact,  that  is  well  known  to  many 
people,  but  which  I  think,  is  overlooked  by  the  general  public;  that  is, 
that  the  line  of  an  oil  field  bears  direct  relation  to  the  price  of  the  product. 
In  other  words,  with  every  advance  in  the  price  per  barrel  there  will  be 
more  barrels  made  available  in  the  form  of  oil  that  cannot  be  produced 
except  at  high  prices.  There  is  a  dead  line,  of  course,  beyond  which  no 
production  will  take  place.  This  dead  line  is  well  illustrated  by  the  prac- 
tice, in  certain  fields,  of  "flooding"  with  water  and  driving  the  oil  to  the 
surrounding  wells.  When  the  surrounding  wells  begin  to  pump  water, 
the  end  has  been  reached,  of  course,  regardless  of  price.  Again,  regard- 
less of  price,  I  think  it  entirely  feasible  to  construct  a  decline  curve  to 
the  point  of  exhaustion.  Whether  the  property  will  operate  in  the  latter 
years  of  this  curve  is  dependent  entirely  on  the  price  at  which  the  product 
can  be  sold. 

CHESTER  W.  WASHBURNE,  New  York,  N.  Y.  (written  discussion). 
Further  explanation  of  Table  1  would  be  appreciated.  It  is  not  clear 
how  a  well  that  declines  from  3000  to  2000  bbl.  a  year  could  produce 
less  than  2000  bbl.;  probably  I  do  not  understand  just  what  the  author's 
figures  represent.  The  comparisons  in  these  tables  and  the  resulting 
conclusions  are  most  useful  in  appraisal  work.  Most  scientific  investi- 
gators, doubtless,  already  have  reached  Professor  Johnson's  seventh 
conclusion :  that  Mid-Continent  wells  will  show  as  long  life  as  Ap- 
palachian wells  of  equal  size.  Moreover,  there  is  every  reason  to 
expect  a  closer  approach  of  price  per  barrel  in  the  two  fields,  and  an 
increase  in  the  "economic  limit"  of  Mid-Continent  wells.  That  region 
is  today  the  best  part  of  the  United  States  in  which  to  buy  oil  lands  on 
current  market  prices  of  production. 

CARL  H.  BEAL,*  San  Francisco,  Calif,  (written  discussion). — The 
value  of  oil  properties  depends  principally  on  the  amount  of  oil  they  will 
produce  and  the  rate  at  which  this  oil  is  to  be  obtained.  This  is  a  self- 
evident  fact  and  requires  no  proof.  Consequently,  such  studies  as  those 
made  by  Mr.  Johnson  are  of  the  greatest  value  and  interest,  for  they 
furnish  a  definite  comparison  of  the  rates  at  which  wells  in  different 
Gelds  will  give  up  their  oil.  Studies  of  this  kind  show  the  importance, 
furthermore,  of  studying  the  effect  of  various  factors  influencing,  and 
controlling  the  amount  of  oil  that  may  be  obtained  from  an  oil  sand,  and 
the  rate  at  which  this  oil  will  be  given  up. 

Mr.  Johnson's  comparison  of  the  rate  at  which  oil  is  obtained  in 
different  fields  would  be  more  illuminating  and  valuable  if  augmented 

*  Petroleum  geologist  and  engineer. 


DISCUSSION  371 


with  a  similar  comparison  of  the  amounts  that  the  different  fields 
produce  per  acre.  Other  factors  being  equal,  the  amount  of  oil  that 
may  be  produced  by  an  acre  of  land  depends  on  the  initial  production 
of  the  wells  drilled  to  this  sand,  and  the  rate  at  which  the  oil  is  produced, 
for  ultimate  production,  under  such  circumstances  is  a  function  of  initial 
production.  These  statistics  may  be  obtained  without  great  difficulty 
from  the  same  data  used  by  Mr.  Johnson  in  the  preparation  of  his  paper; 
in  fact,  such  a  comparison  could  be  made  much  more  easily  than  the 
one  of  the  decline  curves. 

This  study  shows  not  only  the  necessity  of  more  investigation  along 
this  line,  but  the  necessity  of  getting  at  the  fundamental  influences  that 
control  production  in  different  oil  fields.  Certainly  the  variation  shown 
by  Mr.  Johnson  to  exist  can  be  laid  only  to  the  factors  influencing  pro- 
duction, or  the  different  conditions  under  which  the  oil  is  produced  in 
the  oil  fields  of  the  United  States.  If  all  fields  existed  under  the  same 
conditions  originally  and  development  and  production  were  carried  on 
in  the  same  manner,  the  decline  curves  would  be  identical.  As  they  are 
not  identical,  the  conditions  affecting  the  production  of  oil  must  be  dif- 
ferent, for  development  and  production  conditions  are  usually  approxi- 
mately the  same  in  all  fields. 

As  each  decline  curve  possesses  its  particular  shape  because  of  the 
composite  results  of  the  factors  influencing  oil  production,  it  is  essential 
that  we  strive  to  learn  the  effect  of  these  different  factors  on  the  decline 
of  oil  wells,  so  that,  with  a  few  of  the  more  important  factors  known,  we 
can  predict  with  approximate  accuracy  the  decline  of  the  wells  in  a  new 
field.  For  instance,  let  it  be  assumed  that  the  composite  effect  of  all 
the  important  factors  influencing  the  rate  of  production  in  a  certain  field 
is  known,  the  thickness  of  the  oil  sand  is  not  variable,  the  wells  are  spaced 
a  certain  distance,  and  the  depth  is  fairly  uniform.  By  an  analysis  of 
these  data  one  can  determine  in  what  way  almost  any  important  factor 
affects  the  ultimate  production  per  acre,  and  the  rate  at  which  the  oil  is 
obtained.  If  the  influence  of  each  production  factor  in  the  field  can  be 
measured,  the  estimation  of  the  possibilities  of  properties  in  other  fields, 
if  one  or  more  of  the  important  production  factors  are  similar,  will  be 
greatly  facilitated.  The  problem  is  to  determine  the  individual  influences 
of  the  different  factors.  We  already  know  that  certain  production  fac- 
tors have  certain  specific  influences  upon  the  output  of  wells;  for  instance, 
large  initial  production  will  create  a  tendency  toward  a  large  ultimate 
production,  whereas  a  small  initial  production  will  create  a  tendency 
toward  a  small  ultimate  production.  Thick  and  thin  sands  react  in  the 
same  manner,  respectively. 

If  the  individual  effect  of  these  conditions,  or  production  factors,  can 
be  determined,  there  should  be  no  great  difficulty  in  estimating  the  gen- 
eral tendency  that  will  be  followed  by  producing  wells  in  new  fields, 


372  VARIATION  IN  DECLINE  OP  VARIOUS  OIL  POOLS 

providing  some  of  the  more  important  factors  are  known.  For  instance, 
take  the  new  Ranger  field  in  north  Texas.  More  than  a  year  ago  it  was 
evident  to  anyone  familiar  with  the  influences  of  different  production 
factors  that  the  wells  of  Ranger  would  have  a  rapid  decline  and 
produce  but  small  amounts  per  acre.  In  fact,  the  particular  decline  that 
these  wells  would  follow  could  have  been  forecast  with  fair  certainty,  for 
the  reason  that  the  conditions  in  southeastern  Ohio  in  certain  localities 
were  practically  equivalent.  In  the  latter  district,  the  high  rock  pressure, 
probably  due  to  the  great  depth,  and  the  thin  and  rather  porous  sand 
favored  rapid  decline  and  small  ultimate  production.  Unquestionably, 
if  any  new  field  were  found  to  exist  under  approximately  the  same  con- 
ditions, we  could  expect  approximately  the  same  production  rate.  As 
thick  sands  were  not  common  in  Ranger  up  to  a  year  ago  and  as  the  depth 
was  approximately  the  same  as  in  the  southeastern  Ohio  fields,  the  rate 
of  decline  could  be  expected  to  be  approximately  the  same  as  that  found 
in  southeastern  Ohio. 

Mr.  Johnson  proposes  the  hypothesis,  in  his  fifth  conclusion,  that  it 
is  characteristic  of  fields  older  than  Devonian  to  show  poor  persistence. 
Any  such  hypothesis  is  unnecessary.  It  usually  is  a  self-evident  fact 
that  these  fields  will  not  produce  as  much  oil  per  unit  as  the  fields  of 
younger  geological  age.  As  a  rule,  the  oil  is  less  viscous,  the  sands  thinner, 
less  porous,  and  more  compact. 

The  word  " persistence"  is  misleading,  for  it  indicates  length  of  life 
and  the  length  of  life  depends,  to  a  certain  extent,  on  the  price  of  oil.  It 
would  be  better  to  express  the  productiveness  of  fields  in  proportion  per 
acre.  Furthermore,  the  word  persistence,  indicating  length  of  life,  when 
applied  to  fields  is  very  misleading,  for  the  reason  that  the  life  of  a  field 
or  of  a  tract  of  land  is  roughly  proportional  to  the  size  of  the  field,  or  to 
the  size  of  the  tract.  Life  or  persistence  should  not  be  expressed  for  a 
field,  for  the  life  of  a  field  or  of  a  tract  depends  on  the  rate  at  which  that 
field  or  tract  is  drilled  up  and  on  the  margin  of  profit  derived  from  the 
oil.  These  terms  may  easily  be  expressed  to  signify  the  length  of  life  of 
wells,  for  the  production  of  individual  wells  of  limited  life  make  up  the 
production  of  the  tract  or  of  the  field.  The  great  length  of  life  in  some 
eastern  fields  is  due,  first,  to  the  price  of  oil  and,  next,  to  the  size  of  the 
fields  and  the  slowness  of  drilling.  The  life  of  individual  wells  possibly 
has  been  lengthened  by  the  price  of  oil.  Probably  in  very  few  cases 
will  the  life  of  a  well  be  as  long  as  that  of  the  field  or  of  the  tract. 

Mr.  Johnson's  conclusions  on  the  fallacy  of  the  barrel-day  price  of  a 
property  cannot  be  emphasized  too  strongly.  This  method  of  purchasing 
producing  properties  is  a  gage  of  doubtful  value,  and  has  no  engineering 
basis.  As  a  general  rule,  it  will  be  found  that,  as  the  prospects  of  future 
production  become  better,  the  value  of  the  property,  as  determined  by 
the  barrel-day  price,  will  automatically  be  reduced,  for  the  reason  that 


DISCUSSION  373 

the  users  of  this  method  of  valuing  properties  do  not  accurately  gage  the 
quantity  of  future  production  available.  Even  though  the  possibilities 
are  accurately  gaged,  the  value  of  the  oil  in  the  undrilled  portion  of  the 
tract  cannot  be  easily  expressed  in  the  barrel-day  price  without  making 
an  engineering  appraisal.  If  it  were  possible  to  gage  accurately  the 
prospects  of  obtaining  oil  in  the  drilled  and  undrilled  portions  of  the 
tract,  and  the  barrel-day  price  were  raised  or  lowered  accordingly,  such 
a  method  would  be  worth  while.  It  is  not  to  be  denied  that  the  method 
has  some  merit  as  a  rough  gage  of  oil-land  values. 

R.  H.  JOHNSON. — Mr.  Washburne  asks  how  it  is  possible  that  any  of 
these  figures  should  be  less  than  a  year's  production.  The  reason  is  that 
a  year  might  be  represented  by  one  section  of  the  curve  and  another  year 
might  be  represented  by  a  section  of  the  curve  that  overlaps  the  first, 
instead  of  leaving  more  or  less  of  a  gap  outside.  It  means  that  less  than 
a  year  suffices  to  bring  about  the  stated  drop  in  average. 

When  Mr.  Beal  asks  for  the  acre-yield  data,  he  is  asking  for  the 
impossible,  so  far  as  the  manual  is  concerned,  because  it  does  not  give  the 
acreage.  It  was  desirable  to  have  that  information  in  the  manual,  but 
those  who  got  out  the  manual  had  a  large  task  to  accomplish  in  a  limited 
period  of  time,  so  that  the  acre-yield  together  with  other  desirable  data 
could  not  be  obtained. 

I  want  to  make  a  plea  for  that  word  "persistence; "  we  need  a  word  for 
this  attribute,  which  is  extremely  important.  It  is  an  attribute  we  have 
to  talk  about  and  handle,  and  it  seems  to  me  we  should  have  a  name  for 
it.  What  would  be  helpful  would  be  a  better  name,  but  until  we  get  a 
better  one,  we  need  this  one. 

THE  CHAIRMAN  (RALPH  ARNOLD,  Los  Angeles,  Calif.). — The  term 
" persistence  of  a  well"  or  "persistence  of  a  field"  would  overcome  Mr. 
Beal's  criticism. 


374  APPLICATION    OP   TAXATION    REGULATIONS 


Application  of  Taxation  Regulations  to  Oil  and  Gas 

Properties 

BY  THOMAS  Cox,  NEW  YORK,  N.  Y. 

(St.  Louis  Meeting,  September,  1920) 

THIS  paper  makes  no  claim  to  any  new  idea;  it  simply  reviews  the 
Treasury  Department  Regulations  pertaining  to  the  practical  applica- 
tion of  depreciation  and  depletion  and  other  allowances  governing  taxa- 
tion of  oil  and  gas  properties.  Other  methods  may  be  existent,  but  as 
they  may  not  conform  to  the  legal  status  they  must  be  discarded. 

In  complying  with  the  present  laws  governing  the  industry  with  regard 
to  taxation  and  the  allowable  deductions  therefrom,  the  following  con- 
siderations are  essential:  Depletion,  depreciation,  amortization,  other 
allowances,  and  items  not  deductible. 

It  is  definitely  understood  that  depletion  is  the  loss  or  exhaustion  sus- 
tained in  the  continuous  operating  of  an  oil  and  gas  property,  and  that 
each  unit  of  oil  or  gas  taken  out  reduces  the  value  of  the  property  until 
its  final  exhaustion.  Depletion  applies  only  to  the  natural  deposits 
of  oil  and  gas  due  to  their  removal  in  the  course  of  exploitation  of  any 
property. 

Depredation  is  defined  to  cover  the  waste  of  assets  due  to  exhaustion, 
wear  and  tear,  and  obsolescence  of  the  physical  property,  and  is  separate 
and  distinct  from  depletion;  its  allowance  is  that  amount  which  should  be 
set  aside  for  the  taxable  year  in  such  sums  as  for  the  useful  life  of  the 
property  will  suffice  to  repay  its  original  cost — or  its  value  as  of  Mar.  1, 
1913,  if  acquired  by  the  taxpayer  before  that  date — less  the  salvage  value 
at  the  end  of  such  useful  life. 

Amortization  is  allowed  for  such  facilities  as  were  built  or  acquired  on 
or  after  Apr.  6,  1917,  for  the  production  of  articles  contributing  to  the 
prosecution  of  the  war  and,  in  the  case  of  vessels,  those  built  and  acquired 
after  that  date.  The  amount  to  be  extinguished,  in  general,  is  the  excess 
of  the  unextinguished  or  unrecovered  cost  of  the  property  over  its  maxi- 
mum value  under  stable  post-war  conditions. 

Claims  for  amortization  must  be  unmistakably  differentiated  in  the 
returns  from  all  other  claims  of  depreciation.  The  taxpayer  is  also  re- 
quired to  furnish  full  information  with  the  claims  for  amortization  to 
the  full  satisfaction  of  the  Commissioner.  Further  reference  is  directed 
to  the  specific  rules  and  regulations  for  making  these  claims. 


THOMAS   COX  375 

Other  allowances  are:  cost  of  development,  all  operating  expenses, 
repairs,  taxes,  losses,  personal  services,  bonuses  to  employees,  damages, 
abandoned  wells,  same  as  individuals. 

Items  not  deductible  are:  donations  to  employees,  losses  in  illegal 
transactions,  indeterminate  oil  losses,  accrued  deductions  not  charged  in 
prior  years,  depletion  for  past  years. 

ACCOUNTS 

In  order  to  carry  out  the  intention  of  the  Government  regulations, 
and  to  render  the  returns  properly,  it  is  essential  that  books  of  accounts 
be  kept  to  conform  to  the  schedules  issued  by  the  Treasury  Department. 

Every  taxpayer  claiming  and  making  a  deduction  for  depletion  and 
depreciation  of  mineral  property  shall  keep  accurate  ledger  accounts  in 
which  shall  be  charged  the  fair  market  value  as  of  Mar.  1,  1913,  or  within 
30  days  after  the  date  of  discovery,  or  the  cost,  as  the  case  may  be, 
of  the  property,  and  of  the  plant  and  equipment,  together  with  such 
amounts  expended  for  development  of  the  property  or  additions  to  plant 
and  equipment  since  that  date  as  have  not  been  deducted  as  expense  in 
his  returns. 

These  accounts  shall  be  credited  with  the  amount  of  the  depreciation 
and  depletion  deductions  claimed  and  allowed  each  year,  or  the  amounts 
of  the  depreciation  and  depletion  shall  be  credited  to  depletion  and  de- 
preciation reserve  accounts,  to  the  end  that,  when  the  sum  of  the  credits 
for  depletion  and  depreciation  equals  the  value  or  the  cost  of  the  property 
plus  the  amount  added  thereto  for  development  or  additional  plant  and 
equipment,  less  salvage  value  of  the  physical  property,  no  further  de- 
duction for  depletion  and  depreciation  with  respect  to  the  property  will 
be  allowed. 

Because  of  the  fact  that  depreciation  and  depletion  deductions  are 
applied  against  different  capital  sums,  which  are  usually  returnable  at 
different  rates,  it  is  essential  that  these  accounts  be  kept  separately;  that 
is,  the  cost  or  value  of  the  physical  property  subject  to  depreciation  with 
deductions  for  depreciation  enter  into  one  account,  while  the  cost  or  value 
of  the  property  (exclusive  of  physical  property)  together  with  additions 
for  such  development  costs  as  have  not  been  charged  to  current  operating 
expenses  or  deducted  as  depletion,  enter  into  a  separate  account. 

If  dividends  are  paid  out  of  a  depletion  or  depreciation  reserve  the 
stockholders  must  be  expressly  notified  that  the  dividend  is  a  return  of 
capital  and  not  an  ordinary  dividend  out  of  profits. 

It  is,  therefore,  necessary  to  reflect  in  the  books  of  accounts  and 
records  such  items  as  are  required  to  be  filled  in  on  the  Treasury  De- 
partment questionnaire,  in  so  far  as  it  pertains  to  the  taxpayer. 


376  APPLICATION   OF  TAXATION   REGULATIONS 

Maps  that  accompany  the  records  and  statements  must  be  sufficient 
to  show  the  property  in  relation  to  section,  township,  and  range  lines, 
and  should  have  the  name  of  the  state,  company,  or  individual,  scale  of 
map,  date  of  survey,  and  points  of  compass.  All  wells  should  be  located 
and  company  property  designated  to  distinguish  it  from  the  property  of 
adjacent  owners.  The  character  of  the  wells  should  be  properly  indicated 
by  standard  symbols  explained  in  marginal  note. 

ESTABLISHING  VALUE  OF  PROPERTY 
Determination  of  Cost  of  Deposits 

In  any  case  in  which  a  depletion  or  depreciation  deduction  is  computed 
on  the  basis  of  the  cost  or  price  at  which  any  mine,  mineral  deposit,  min- 
eral rights,  or  leasehold  was  acquired,  the  owner  or  lessee  will  be  required, 
upon  request  of  the  Commissioner,  to  show  that  the  cost  or  price  at  which 
the  property  was  bought  was  fixed  for  the  purpose  of  a  bona-fide  pur- 
chase and  sale,  by  which  the  property  passed  to  an  owner,  in  fact  as  well 
as  in  form,  different  from  the  vendor. 

No  fictitious  or  inflated  cost  or  price  will  be  permitted  to  form  the 
basis  of  any  calculation  of  a  depletion  or  depreciation  deduction,  and  in 
determining  whether  or  not  the  price  or  cost  at  which  any  purchase  or 
sale  was  made  represented  the  actual  market  value  of  the  property  sold, 
due  weight  will  be  given  to  the  relationship  or  connection  existing  between 
the  person  selling  the  property  and  the  buyer  thereof. 

Determination  of  Fair  Market  Value 

A  determination  of  the  fair  market  value  of  an  oil  or  gas  property 
(or  the  taxpayer's  interest  therein)  is  required : 

1.  In   connection   with  the   computation  of  depletion  allowances: 
(a)  As  of  Mar.  1,  1913,  in  the  case  of  properties  acquired  prior  to  that 
date;  and  (6)  at  the  date  of  discovery,  or  within  30  days  thereafter,  in  the 
case  of  oil  and  gas  wells,  discovered  by  the  taxpayer  on  or  after  Mar.  1, 
1913,  and  not  acquired  as  the  result  of  purchase  of  a  proven  tract  or  lease 
where  the  fair  market  value  of  the  property  is  disproportionate  to 
the  cost. 

2.  In  connection  with  computing  the  amount  that  may  be  included 
in  paid-in  surplus,  as  of  date  of  conveyance,  where  the  tangible  property 
has  been  conveyed  to  a  corporation  by  gift  or  at  a  value  accurately  es- 
tablished or  definitely  known  as  at  date  of  conveyance  clearly  and  sub- 
stantially in  excess  of  the  cash  or  of  the  par  value  of  the  stock  or  shares 
paid  therefor. 

3.  In  connection  with  the  computation  of  profit  and  loss  from  sale  of 
capital  assets  in  the  case  of  properties  acquired  prior  to  Mar.  1,  1913. 


THOMAS   COX  377 

Where  the  fair  market  value  of  the  property  at  a  specified  date,  in 
lieu  of  the  cost  thereof,  is  the  basis  for  depletion  and  depreciation  de- 
ductions, such  value  must  be  determined,  subject  to  approval  or  revision 
by  the  Commissioner,  by  the  owner  of  the  property  in  the  light  of  con- 
ditions and  circumstances  known  at  that  date,  regardless  of  later  dis- 
coveries or  developments  in  the  property  or  in  the  methods  of  extraction. 

No  rule  or  method  of  determining  the  fair  market  value  of  mineral 
property  is  prescribed,  but  the  Commissioner  will  lend  due  weight  and 
consideration  to  any  or  all  factors  and  evidence  having  a  bearing  on  the 
market  value,  such  as:  (a)  Cost,  (6)  actual  sales  and  transfers  of  similar 
properties,  (c)  market  value  of  stock  or  shares,  (d)  royalties  and  rentals, 
(e)  value  fixed  by  the  owner  for  the  purposes  of  the  capital  stock  tax, 
(/)  valuation  for  local  or  state  taxation,  (g)  partnership  accountings, 
(h)  records  of  litigation  in  which  the  value  of  the  property  was  in  question, 
(i)  the  amount  at  which  the  property  may  have  been  inventoried  in  pro- 
bate court,  (j)  disinterested  appraisals  by  approved  methods,  (k)  other 
factors. 

The  decline  curve  method  is  one  of  the  most  reliable  for  making  ap- 
praisals of  oil  properties.  By  this,  one  can  estimate  and  compute  the 
recoverable  oil  contents  of  the  property  and  thus  arrive  at  a  reasonable 
unit  cost  for  making  the  proper  annual  depletion  charge.  This  method 
has  been  tested  and  has  proved  efficient  and  acceptable.  A  constant  record 
is  thus  provided  for  all  future  variations  and  additions  to  the  property. 

REVALUATION  OF  PROPERTY  NOT  PERMITTED 

The  cost  of  the  property  or  its  fair  market  value  at  a  specified  date, 
as  the  case  may  be,  plus  subsequent  charges  to  capital  sum  not  deductible 
as  current  expenses,  will  be  the  basis  for  determining  the  depletion  and 
depreciation  deductions  for  each  year  during  the  continuance  of  the 
ownership  under  which  the  fair  market  value  or  cost  was  fixed;  and  during 
such  ownership  there  can  be  no  revaluation  for  the  purpose  of  this  de- 
duction. This  rule  will  not  forbid  the  redistribution  of  the  capital  sum 
over  the  number  of  units  remaining  in  the  property,  where  erroneous 
estimates  have  been  revised  with  the  approval  of  the  Commissioner. 

Valuation  of  Fee  under  Lease 

The  valuation  of  a  fee  ownership  in  oil  or  gas  land  under  lease  ac- 
quired prior  to  Mar.  1,  1913,  will  have  to  do  with  the  equity  in  its  oil  and 
gas  contents  remaining  to  the  owner  of  the  fee  title  after  deducting  the 
value  of  the  lessee's  rights.  But  subsequent  investments  or  discoveries 
by  the  lessee  will  not  affect  the  lessor's  valuation. 


378  APPLICATION   OF  TAXATION   REGULATIONS 

Proof  of  Discovery  and  Allowances 

The  following  articles  in  Regulations  45  have  been  amended  in  Treas- 
ury Decision  2956,  to  read  as  follows: 

'  Article  220,  Oil  and  Gas  Wells.— Section  214  (a)  (10)  and  section  234  (a)  (9)  pro- 
vide that  taxpayers  who  discover  oil  and  gas  wells  on  or  after  Mar.  1,  1913,  may, 
under  the  circumstances  therein  prescribed,  determine  the  fair  market  value  of  such 
property  at  the  date  of  discovery  or  within  30  days  thereafter  for  the  purpose  of  as- 
certaining allowable  deductions  for  depletion.  Before  such  valuation  may  be  made 
the  statute  requires  that  two  conditions  precedent  be  satisfied: 

(1)  That  the  fair  market  value  of  such  property  (oil  and  gas  wells)  on  the  date  of 
discovery  or  within  30  days  thereafter  became  materially  disproportionate  to  the  cost, 
by  virtue  of  the  discovery,  and 

(2)  that  such  oil  and  gas  wells  were  not  acquired  as  the  result  of  purchase  of  a 
proven  tract  or  lease. 

Article  220  (a)  Discovery,  Proven  Tract  or  Lease,  Property  Disproportionate  Value. — 
(1)  For  the  purpose  of  these  sections  of  the  Revenue  Act  of  1918,  an  oil  or  gas  well 
may  be  said  to  be  discovered  when  there  is  either  a  natural  exposure  of  oil  or  gas,  or 
a  drilling  that  discloses  the  actual  and  physical  presence  of  oil  or  gas  in  quantities 
sufficient  to  justify  commercial  exploitation.  Quantities  sufficient  to  justify  com- 
mercial exploitation  are  deemed  to  exist  when  the  quantity  and  quality  of  the  oil  or 
gas  so  recovered  from  the  weH  are  such  as  to  afford  a  reasonable  expectation  of  at 
least  returning  the  capital  invested  in  such  well  through  the  sale  of  the  oil  or  gas,  or 
both,  to  be  derived  therefrom. 

(2)  A  proven  tract  or  lease  may  be  a  part  or  the  whole  of  a  proven  area.  A  proven 
area  for  the  purpose  of  this  statute  shall  be  presumed  to  be  that  portion  of  the  pro- 
ductive sand  or  zone  or  reservoir  included  hi  a  square  surface  area  of  160  acres  having 
as  its  center  the  mouth  of  a  well  producing  oil  or  gas  hi  commercial  quantities.  In 
other  words,  a  producing  well  shall  be  presumed  to  prove  that  portion  of  a  given  sand, 
zone  or  reservoir  which  is  included  in  an  area  of  160  acres  of  land,  regardless  of  private 
boundaries.  The  center  of  such  square  area  shall  be  the  mouth  of  the  well,  and  its 
sides  shall  be  parallel  to  the  section  lines  established  by  the  United  States  system  of 
public-land  surveys  in  the  District  hi  which  it  is  located.  Where  a  district  is  not 
covered  by  the  United  States  land  surveys,  the  sides  of  said  area  shall  run  north  and 
south,  east  and  west. 

So  much  of  a  taxpayer's  tract  or  lease  as  lies  within  an  area  proven 
either  by  himself  or  by  another  is  a  "  a  proven  tract  of  lease/'  as  contem- 
plated by  the  statute,  and  the  discovery  of  a  well  thereon  will  not  entitle 
such  taxpayer  to  revalue  such  well  for  the  purpose  of  depletion  allowances, 
unless  the  tract  or  lease  had  been  acquired  before  it  became  proven.  And 
even  though  a  well  is  brought  in  on  a  tract  or  lease  not  included  in  a 
proven  area  as  heretofore  defined,  it  may  not  entitle  the  owner  of  the 
tract  or  lease  in  which  such  well  is  located  to  revaluation  for  depletion 
purposes,  if  such  tract  or  lease  lies  within  a  compact  area  which  is  im- 
mediately surrounded  by  proven  land  and  the  geologic  structural  condi- 
tions on  or  under  the  land  so  enclosed  may  reasonably  warrant  the  belief 
that  the  oil  or  gas  of  the  proven  areas  extends  thereunder.  Under  no 
circumstances  is  the  entire  area  to  be  regarded  as  proven  land. 


THOMAS   COX  379 

(3)  The  property  which  may  be  valued  after  discovery  is  the  well.     For  the  pur- 
poses of  these  sections  the  well  is  the  drill  hole,  the  surface  necessary  for  the  drilling 
and  operation  of  the  well,  the  oil  or  gas  content  of  the  particular  sand,  zone  or  reser- 
voir (limestone,  breccia,  crevice,  etc.)  in  which  the  discovery  was  made  by  the  drill- 
ing and  from  which  the  production  is  drawn,  to  the  limit  of  the  taxpayer's  private 
bounding  lines,  but  not  beyond  the  limits  of  the  proven  area  as  heretofore  provided. 

(4)  A  taxpayer  to  be  entitled  to  revalue  his  property  after  Mar.  1,  1913,  for  the 
purpose  of  depletion  allowances  must  make  a  discovery  after  said  date  and  such  dis- 
covery must  result  in  the  fair  market  value  of  the  property  becoming  disproportionate 
to  the  cost.     The  fair  market  value  of  the  property  will  be  deemed  to  have  become 
disproportionate  to  the  cost,  when  the  output  of  such  well  of  oil  or  gas  affords  a  rea- 
sonable expectation  of  returning  to  the  taxpayer  an  amount  materially  in  excess 
of  the  cost  of  the  land  or  lease  if  acquired  since  Mar.  1, 1913,  or  its  fair  market  value  on 
Mar.  1,  1913,  if  acquired  prior  thereto,  plus  the  cost  of  exploration  and  development 
work  to  the  time  the  well  was  brought  in. 

Article  221,  Proof  of  Discovery  of  Oil  and  Gas  Wells. — In  order  to  meet  the  require- 
ments of  the  preceding  article  to  the  satisfaction  of  the  Commissioner,  the  taxpayer 
will  be  required,  among  other  things,  to  submit  the  following  with  his  return: 

A  map  of  convenient  scale,  showing  the  location  of  the  tract  and  discovery  well 
in  question  and  of  the  nearest  producing  well,  and  the  development  for  a  radius  of  at 
least  3  mi.  from  the  tract  in  question,  both  on  the  date  of  discovery  and  on  the  date 
when  the  fair  market  value  was  set. 

A  certified  copy  of  the  log  of  the  discovery  well,  showing  the  location,  the  date 
drilling  began,  the  date  of  completion  and  the  beginning  of  production,  the  formations 
penetrated,  the  oil,  gas  and  water  sands  penetrated,  the  casing  records,  including  the 
record  of  perforations,  and  any  other  information  tending  to  show  the  condition  of  the 
well  and  the  location  of  the  sand  or  zone  from  which  the  oil  or  gas  is  produced  on 
date  discovery  was  claimed. 

A  sworn  record  of  production,  clearly  proving  the  commercial  productivity  of  the 
discovery  well. 

A  sworn  copy  of  the  records,  showing  the  cost  of  the  property. 

A  full  explanation  of  the  method  of  determining  the  value  on  the  date  of  discovery 
or  within  30  days  thereafter,  supported  by  satisfactory  evidence  of  the  fairness  of 
this  value. 

INVESTED  CAPITAL 

The  invested  capital  is  defined  in  section  326  of  the  Revenue  Act 
of  1918,  as:  Actual  cash  bona  fide  paid  in  for  stock  or  shares;  cash  value 
of  property,  other  than  cash,  bona  fide  paid  in  for  stock  or  shares  (as 
limited  by  the  statute);  and  paid-in  or  earned  surplus  and  undivided 
profits,  not  including  surplus  and  undivided  profits  earned  during  the 
year.  The  surplus  and  undivided  profits,  if  not  correctly  reflected  in 
the  taxpayer's  accounts,  may  be  adjusted  in  accordance  with  the  regu- 
lations. These  considerations  are  shown  in  the  paragraphs  relating  to 
surplus  and  undivided  profits. 

Surplus  and  Undivided  Profits,  Allowance  for  Depletion  and  Deprecia- 
tion.— Depletion,  like  depreciation,  must  be  recognized  in  all  cases  in 
which  it  occurs.  Depletion  attaches  to  each  unit  of  mineral  or  other 
property  removed,  and  the  denial  of  a  deduction  in  computing  net  income 


380  APPLICATION    OP  TAXATION   REGULATIONS 

under  the  Act  of  Aug.  5,  1909,  or  the  limitation  upon  the  amount  of  the 
deduction  allowed  under  the  Act  of  Oct.  3, 1913,  does  not  relieve  the  corpo- 
ration of  its  obligation  to  make  proper  provision  for  depletion  of  its 
property  in  computing  its  surplus  and  undivided  profits. 

Adjustments  in  respect  of  depreciation  or  depletion  in  prior  years  will 
be  made  or  permitted  only  on  the  basis  of  affirmative  evidence  that  at 
the  beginning  of  the  taxable  year  the  amount  of  depreciation  or  depletion 
written  off  in  prior  years  was  insufficient  or  excessive,  as  the  case  may  be. 
Where  deductions  for  depreciation  or  depletion  have  either  on  the  books 
of  the  corporation  or  in  its  returns  of  net  income  been  included  in  the 
past  in  expense  or  other  accounts,  rather  than  specifically  as  depreciation 
or  depletion,  or  where  capital  expenditures  have  been  charged  to  expense 
in  lieu  of  depreciation  or  depletion,  a  statement  indicating  the  extent  to 
which  this  practice  has  been  carried  should  accompany  the  return. 

Surplus  and  Undivided  Profits  Reserves  for  Depreciation  or  Depletion. 
If  any  reserves  for  depreciation  or  for  depletion  are  included  in  the 
surplus  account,  the  account  should  be  analyzed  so  as  to  separate  re- 
serves and  leave  only  real  surplus.  Reserves  for  depreciation  or  deple- 
tion cannot  be  included  in  the  computation  of  invested  capital,  except 
to  the  following  extent:  Excessive  depletion  or  depreciation  included 
therein  and  which,  if  charged  off,  could  be  restored  under  article  340 
may  be  included  in  the  computation  of  invested  capital;  and  where  de- 
preciation or  depletion  is  computed  on  the  value  as  of  Mar.  1,  1913, 
or  as  of  any  subsequent  date,  the  proportion  of  depreciation  or  depletion 
representing  the  realization  of  appreciation  of  value  at  Mar.  1,  1913, 
or  such  subsequent  date  may,  if  undistributed  and  used  or  employed  in 
the  business,  be  treated  as  surplus  and  included  in  the  computation  of 
invested  capital. 

For  the  purpose  of  computing  invested  capital,  depreciation  or  de- 
pletion computed  on  the  value  as  of  Mar.  1, 1913,  or  as  of  any  subsequent 
date,  shall,  if  such  value  exceeded  cost,  be  deemed  a  pro  rata  realization 
of  cost  and  appreciation  and  be  apportioned  accordingly.  Except  as 
above  provided,  value  appreciation  (even  though  evidenced  by  an 
appraisal)  that  has  not  been  actually  realized  and  reported  as  income  for 
the  purpose  of  the  income  tax  cannot  be  included  in  the  computation  of 
invested  capital  and,  if  already  reflected  in  the  surplus  account,  it  must 
be  deducted  therefrom. 

The  term  capital  sum  is  here  applied  to  the  total  amount  returnable 
to  the  taxpayer  through  depletion,  depreciation  and  obsolescence  al- 
lowances. It  is  to  be  clearly  distinguished  from  the  term  invested 
capital,  which  is  the  basis  for  the  determination  of  war-profits  credits 
and  excess-profits  credits  of  corporations.  Invested  capital  is  the  actual 
cash,  or  its  equivalent,  paid  in  plus  undistributed  surplus  profits,  and  no 
appreciation  in  the  value  of  any  asset  may  be  included  except  as  provided 
in  article  844  (2). 


THOMAS   COX  381 

Where  amortization  is  allowed,  such  sum  cannot  be  restored  to  the 
invested  capital  for  the  purpose  of  the  war-profits  and  excess-profits 
tax,  nor  any  portion  of  the  amount  covered  by  such  allowance. 


Capital  Sum  and  Invested  Capital 

The  capital  sum  has  no  necessary  relation  to  the  invested  capital. 
It  may  represent  the  investment  of  funds  belonging  to  the  taxpayer,  or 
the  investment  of  borrowed  funds,  which  have  no  relation  to  invested 
capital;  under  the  provisions  of  the  law  and  regulations,  the  capital  sum 
may  include  amounts  based  on  the  right  of  valuation  as  of  Mar.  1,  1913, 
or  within  30  days  after  the  discovery  of  oil  or  gas  by  the  taxpayer. 

Where  such  valuations  are  allowable,  they  have  no  application  to 
invested  capital,  except  in  accordance  with  subdivision  (2)  in  the  pre- 
ceding paragraph  pertaining  to  surplus  and  undivided  profits  reserve 
for  depreciation  or  depletion,  and  may  not  be  used  for  any  purpose  other 
than  as  a  basis  on  which  to  determine  the  gain  or  loss  arising  from  the 
sale  or  surrender  of  property  acquired  prior  to  Mar.  1,  1913.  With  re- 
spect to  any  allowance  for  amortization,  the  basis  is  the  cost  of  the  prop- 
erty acquired  after  Apr.  5, 1917,  and  no  amount  may  be  added  on  account 
of  revaluation. 

Certain  deductions  from  gross  income  are  based  on  the  capital  sum; 
credits  are  based  on  invested  capital.  It  is  necessary  that  these  terms  be 
clearly  understood  by  the  taxpayer  in  order  to  avoid  confusion  in  making 
returns.  In  general,  the  deductions  from  gross  income  allowed  corpora- 
tions are  the  same  as  allowed  individuals,  except  that  corporations  may 
deduct  dividends  received  from  other  corporations  subject  to  the  tax  and 
may  not  deduct  charitable  contributions. 


DETERMINATION  OF  QUANTITY  OF  OIL  IN  GROUND 

In  the  case  of  either  an  owner  or  lessee,  it  will  be  required  that  an 
estimate,  subject  to  the  approval  of  the  Commissioner,  shall  be  made  of 
the  probable  recoverable  oil  contained  in  the  territory  with,  respect  to 
which  the  investment  is  made  as  of  the  time  of  purchase,  or  as  of  Mar.  1, 
1913,  if  acquired  prior  to  that  date,  or  within  30  days  after  the  date  of 
discovery,  as  the  case  may  be.  The  oil  reserves  must  be  estimated  for 
undeveloped  proven  land  as  well  as  producing  land.  If  information  sub- 
sequently obtained  clearly  shows  the  estimate  to  have  been  materially 
erroneous,  it  may  be  revised  with  the  approval  of  the  Commissioner. 

The  estimate  of  probable  recoverable  oil  in  the  ground  is  fundamen- 
tally necessary  if  a  reasonable  deduction  for  depletion  is  to  be  calculated 
and,  while  it  may  be  impossible  to  determine  exactly  the  future  produc- 


382  APPLICATION   OF  TAXATION   REGULATIONS 

tion  of  a  well  or  tract,  it  has  been  found  possible  to  predict  future  pro- 
ductions with  a  comparatively  narrow  limit  of  error.  The  result  of 
analysis  of  a  great  volume  of  production  records  has  led  to  the  develop- 
ment of  the  methods  suggested  in  the  following  paragraphs.  It  is  good 
practice  to  reduce  estimates  to  the  per  acre  basis  of  the  contents  of  the 
well;  this  affords  a  reasonable  check  on  such  estimates. 

METHODS  OP  ESTIMATING  RECOVERABLE  RESERVES 

The  Treasury  Department  does  not  prescribe  any  particular  method 
of  estimating  recoverable  reserves,  but  the  methods  described  herein 
are  suggested  as  applicable  to  a  wide  variety  of  conditions.  The  under- 
lying principle  of  the  methods  outlined  is  that  the  best  indication  of  the 
future  production  of  any  well  is  to  be  found  in  the  history  of  similar  wells 
in  the  same  or  similar  districts,  and  that,  other  things  being  equal,  a 
well's  production  is  more  likely  to  approximate  the  production  of  a  simi- 
lar well  in  the  tract  or  district  than  to  deviate  widely  from  the  average. 
The  method  may  be  summarized  as  follows: 

1.  Plotting  the  record  of  production  of  individual  wells,  or,  lacking 
such  detailed  information,  the  average  production  per  well  for  each  tract. 

2.  Deriving  from  these  graphical  records  an  average  or  composite 
production  decline  curve  for  the  district. 

3.  Estimating  from  the  last  year's  average  production  per  well  the 
probable  future  production,  based  on  the  average  production  decline 
curve,  or  a  future  production  curve  derived  from  the  production  decline 
curve. 

4.  Ascertaining  probable  total  future  production  of  producing  wells 
by  multiplying  average  future  production  per  well  by  the  number  of  wells 
producing  at  the  end  of  the  year. 

5.  Estimating  the  probable  future  production  of  undeveloped  proven 
land  on  the  basis  of  nearby  production,  making  due  allowance  for  the 
decline  in  pressure  due  to  the  extraction  of  oil  from  the  pool. 

It  is  to  be  emphasized  that  the  value  of  estimates  will  depend  almost 
entirely  on  the  skill  with  which  the  method  is  carried  out  and  the  char- 
acter of  the  production  records  on  which  they  are  based.  Where  accurate 
detailed  records  are  not  kept,  it  may  be  difficult  to  determine  a  reasonable 
allowance  for  depletion. 

The  taxpayer  may  estimate  his  recoverable  reserves  by  any  method 
that  can  be  shown  to  be  well  founded,  but  in  all  cases  the  data  on  which 
such  estimate  was  based  must  be  submitted,  with  a  description  of  the 
method  employed,  and  a  resume*  of  the  calculations. 

COMPUTATION  OF  ALLOWANCE  FOR  DEPLETION  OF  OIL  WELLS 

When  the  cost  or  value  as  of  Mar.  1,  1913,  or  within  30  days  after  the 
date  of  discovery  of  the  property,  shall  have  been  determined  and  the 


THOMAS   COX  383 

number  of  mineral  units  in  the  property  as  of  the  date  of  acquisition  or 
valuation  shall  have  been  estimated,  the  division  of  the  former  amount  by 
the  latter  figure  will  give  the  unit  value  for  the  purposes  of  depletion,  and 
the  depletion  allowance  for  the  taxable  year  may  be  computed  by  multi- 
plying such  unit  value  by  the  number  of  units  of  mineral  extracted  during 
the  year.  If,  however,  proper  additions  are  made  to  the  capital  account 
represented  by  the  original  cost  or  value  of  the  property,  or  circumstances 
make  advisable  a  revised  estimate  of  the  number  of  mineral  units  in  the 
ground,  a  new  unit  value  for  purposes  of  depletion  may  be  found  by  di- 
viding the  capital  account  at  the  end  of  the  year,  less  deductions  for  de- 
pletion to  the  beginning  of  the  taxable  year  which  have  or  should  have 
been  taken,  by  the  number  of  units  in  the  ground  at  the  beginning  of  the 
taxable  year.  This  number,  unless  a  revision  of  the  original  estimate  has 
been  made,  will  equal  the  number  of  units  in  the  ground  at  the  date  of 
original  acquisition  or  valuation,  less  the  number  extracted  prior  to  the  tax- 
able year.  If,  however,  recalculation  is  made,  the  number  of  units  at  the 
beginning  of  the  year  will  be  the  sum  of  the  gross  production  of  the  year 
and  the  estimated  mineral  reserves  in  the  property  at  the  end  of  the  year. 

Each  barrel  of  oil  or  unit  of  gas  extracted  and  marketed  must,  before 
a  profit  can  be  realized,  pay  not  only  its  proportionate  share  of  the  oper- 
ating expense  and  deductions  for  depreciation  and  obsolescence  of  physi- 
cal property,  but  also  must  pay  its  proportionate  share  of  capital  sum 
returnable  through  depletion  allowances.  This  proportionate  share  of 
capital  sum  returnable  through  depletion  allowances  that  each  unit  of 
oil  or  gas  must  pay  is  unit  cost. 

Unit  cost  is  obtained  by  dividing  the  capital  sum  returnable  through 
depletion  by  the  estimated  recoverable  reserve  at  the  beginning  of  the 
taxable  year.  The  depletion  deduction  is  computed  by  multiplying  the 
unit  cost  by  the  number  of  units  produced  during  the  taxable  year. 

It  is  to  be  noted  that  the  estimated  recoverable  reserves  and  the  num- 
ber of  units  produced  are  used  in  estimating  the  depletion  deduction  for 
both  lessor  and  lessee.  Since,  however,  they  are  applied  to  different 
capital  amounts  returnable  through  depletion  deductions,  the  unit  costs  for 
lessee  and  lessor  are  not  identical,  and  the  deductions  bear  the  same  ratio 
as  the  capital  sum  of  lessor  and  lessee.  Usually  the  lessee's  investment  is 
greater  than  the  lessor's  and  his  deductions  are  correspondingly  greater. 
Stated  in  another  way,  if  a  certain  proportionate  part  of  the  lessee's 
capital  returnable  through  depletion  deductions  is  deducted  in  a  given 
year,  the  same  proportion  of  the  lessor's  capital  sum  returnable  through 
depletion  will  be  deducted. 

Computation  of  Depletion  Allowance  for  Combined  Holdings  of  Oil  Properties 

The  recoverable  oil  belonging  to  the  taxpayer  shall  be  estimated  sep- 
arately on  the  smallest  unit  on  which  data  are  available,  such  as  individual 


384  APPLICATION    OF   TAXATION   REGULATIONS 

wells  or  tracts,  and  these,  added  together  into  a  grand  total,  are  to  be 
applied  to  the  total  capital  assets  returnable  through  depletion.  The 
capital  sum  shall  include  the  cost  or  value,  as  the  case  may  be,  of  all  oil 
rights,  freeholds,  or  leases,  plus  all  incidental  costs  of  development  not 
charged  as  expense.  The  unit  multiplied  by  the  total  number  of  units 
of  oil  produced  by  the  taxpayer  during  the  taxable  year  from  all  of  the 
oil  properties  will  determine  the  amount  that  may  be  allowably  deducted 
from  the  gross  income  of  that  year.  In  the  case  of  sale  of  particular 
tracts,  full  account  must  be  taken  of  the  depletion  of  such  tracts  in  com- 
puting profit  or  loss  thereon. 

A  convenient  summary  record  may  be  kept  of  acreage  and  production 
with  average  decline  curves  of  wells  if  leases  are  contiguous,  or  if  property 
consists  of  many  separate  leases  or  districts,  one  curve  should  be  made  for 
each.  Such  a  summary  form  would  be  a  permanent  record  and  greatly 
assist  in  making  up  the  annual  returns.  Each  lease  having  its  own  de- 
cline curve  and  production  can  be  balanced  out  with  the  reserves  at  the 
end  of  each  year.  New  additions  brought  in  during  the  year  must  be 
added  and  carried  out  in  accordance  with  the  general  plan. 

COMPUTATIONS  OF  ALLOWANCE  FOR  DEPLETION  OF  GAS  WELLS 

The  deductions  allowed  in  computing  income  from  natural-gas  prop- 
erties are  in  general  similar  to  those  allowed  oil  operators,  but  the  method 
of  computing  the  deductions  and  the  various  assets  differ  in  certain 
particulars,  the  most  notable  of  which  are  involved  in  the  problems  of 
estimating  the  probable  reserves  and  computing  the  depletion.  On 
account  of  the  peculiar  conditions  surrounding  the  production  of  natural 
gas,  it  is  necessary  to  compute  the  depletion  allowance  for  gas  properties 
by  methods  suitable  to  the  particular  cases.  Usually  the  depletion  should 
be  computed  on  the  basis  of  decline  in  closed  or  rock  pressure,  taking  into 
account  the  effects  of  water  encroachment  and  any  other  modifying 
factors.  In  many  fields,  more  or  less  additional  evidence  on  depletion  is 
to  be  had  from  such  considerations  as:  Details  of  production  and  per- 
formance records  of  well  or  properties;  decline  in  open  flow  capacity; 
comparison  with  the  life  histories  of  similar  wells  or  properties,  particu- 
larly those  now  exhausted;  and  size  of  reservoir  and  pressure  of  gas. 

Methods  of  Computing  Gas  Depletion 

Gas  depletion  may  be  computed  from  the  details  of  production  or  the 
performance  record  of  the  well  or  property,  estimating,  from  its  best 
records,  the  quantity  the  well  may  be  expected  to  produce  and  also  the 
rate  of  production.  The  decline  in  open  flow  capacity  indicates  the  rate 
of  exhaustion. 

Depletion  may  also  be  computed  by  a  comparison  with  the  life  history 


THOMAS   COX  385 

of  similar  wells  or  properties,  particularly  those  exhausted  or  nearing 
exhaustion;  also  by  comparing  the  size  of  the  reservoir  and  the  pressure 
of  gas  or  by  the  pore  space  method.  The  factors  that  make  this  method 
difficult  to  apply  are  the  difficulties  of  accurately  ascertaining  the  thick- 
ness of  pay,  limits  of  pool,  percentage  of  pore  space,  effect  of  encroach- 
ing oil  or  water,  and  the  quantity  of  gas  remaining  when  production  is 
no  longer  possible. 

Other  indications  of  depletion  are  the  decreasing  supply  by  general 
observation,  by  minute  pressure  changes,  and  by  line  pressure  observed  at 
compressing  stations.  The  appearance  of  water  or  oil  in  a  gas  well  may 
be  the  significant  symptom  of  the  approaching  termination  of  the  life  of 
the  well.  Clogging  by  paraffine,  salt,  or  other  deposits  may  demand  the 
modification  of  depletion  estimates. 

Closed,  or  Rock,  Pressure  Method 

This  is  the  best  method  of  estimating  the  depletion  of  gas  properties 
as  the  rock  pressure  can  be  ascertained  with  a  fair  degree  of  accuracy,  and 
the  pressure  decline  established,  based  on  Boyles'  law.  In  gaging,  care 
must  be  taken  to  insure  that  the  gage  is  accurate;  it  should  be  tested  both 
before  and  after  being  attached  to  the  well.  Care  must  also  be  taken 
to  empty  the  well  of  oil  and  water  and  the  well  should  be  closed  long 
enough  to  allow  the  pressure  to  build  up  to  its  maximum. 

Several  corrections  and  refinements  are  made  in  applying  this  method 
to  the  computation  of  depletion;  it  does  not  afford  data  on  the  amount  of 
gas  originally  in  the  pool,  but  only  the  portion  of  the  gas  that  has  been 
removed.  The  atmospheric  pressure  must  be  taken  into  consideration 
when  taking  the  difference  of  gage,  adding  the  same  to  each  condition 
in  making  the  fraction  remaining  in  the  ground.  Account  should  also  be 
taken  of  pressures  at  which  wells  are  abandoned  in  the  district. 

Unit  Cost  as  Applied  to  Natural  Gas 

The  unit-cost  method  can  be  used  by  regarding  pounds  of  closed 
pressures  as  units,  for  the  actual  quantity  of  gas  commonly  varies  with 
the  decline  in  pressure.  The  relative  quantities  at  the  beginning  and 
end  of  the  tax  year,  and  at  the  time  of  abandonment,  may  be  used  for 
tax  purposes  when  better  information  is  lacking. 

Apportionment  of  Depletion  Among  Various  Sands 

Where  more  than  one  sand  under  a  property  is  yielding  gas,  the  prob- 
lem arises  as  to  how  to  weight  or  evaluate  the  decline  in  pressure  in  the 
different  sands.  The  depletion  sustained  is  not  indicated  by  the  average 
decline  in  pressure,  but  is  more  nearly  proportionate  to  the  decline  in  the 
good  sand.  If  accurate  figures  on  capacities  of  wells  are  obtainable,  it 
will  be  possible  to  make  a  fairly  accurate  weighting  of  the  pressure  de- 

VOL.  LXV. 25. 


386  APPLICATION   OF  TAXATION   REGULATIONS 

clines;  or  if  facts  indirectly  indicating  capacity  of  individual  wells  are 
obtainable,  some  light  may  be  thrown  on  the  question.  But,  as  a  general 
rule,  it  is  necessary  to  average  the  decline  of  wells  drawing  from  differ- 
ent sands  as  though  they  were  drawing  from  the  same  sand. 

Testing  is  recommended  in  summer  or  early  fall.  Abandoned  wells 
may  be  regarded  as  fully  depleted  and  their  pressure  counted  as  zero  in 
computing  depletion.  It  is  suggested  that  the  capital  sum  at  the  be- 
ginning of  each  year  be  treated  as  100  per  cent.,  for  the  average  pressure 
at  the  beginning  of  the  year  and  the  average  decline  during  the  year  will 
then  furnish  a  readily  usable  basis  for  computing  the  depletion  allowance. 

The  following  formula  has  been  recommended  for  use  by  the  Treasury 
Department: 

if 

-  X  2  =  Depletion  allowance 

in  which  x  =  capital  sum  to  end  of  the  year;  y=  total  future  pressure  de- 
cline, or  difference  between  sum  of  pressures  at  beginning  of  the  tax  year 
and  the  sum  of  pressures  at  time  of  expected  abandonment;  z  =  pressure 
decline  during  year  as  obtained  by  adding  to  sum  of  pressures  at  begininng 
of  year  the  sum  of  pressures  of  any  new  wells  completed  during  year  and 
subtracting  sum  of  pressures  at  end  of  year. 
The  formula  may  also  be  written  as  follows: 

Capital  sum  to  the  end  Sum  of  pressures  at  be- 

of  tax  year  ginning   of   tax   year  + 

Sum  of  pressures  at  be-  x  sum  of  pressures  of  new  =  Depletion  allowance. 

ginning  of  year  —  sum  of  wells  —  sum  ol  pressures 

pressures  at  time  of  ex-  at  end  of  tax  year 

pected  abandonment 

The  regulations  require  gas-well  pressure  records  to  be  kept,  and  where 
the  field  is  too  new  to  determine  the  quantity  in  reserve  a  tentative  esti- 
mate will  apply  until  production  figures  are  available  from  which  an 
accurate  estimate  may  be  made. 

Computation  of  Depletion  Allowance  for  Combined  Holdings  of 
Gas  Properties 

In  the  case  of  gas  properties,  the  depletion  allowance  for  each  pool 
may  be  computed  by  using  the  combined  capital  sum  returnable  through 
depletion  of  all  tracts  of  gas  land  owned  by  the  taxpayer  in  the  pool  and 
the  average  decline  in  rock  pressure  of  all  the  taxpayer's  wells  in  each  pool 
in  the  formula  given  in  article  211.  The  total  allowance  for  depletion 
of  the  gas  properties  of  the  taxpayer  will  be  the  sum  of  the  amounts  com- 
puted for  each  pool. 


THOMAS   COX  387 

The  depletion  of  gas  supplies  belonging  to  a  taxpayer  may  be  more 
accurately  computed  by  making  estimates  for  each  tract,  though  it  is  quite 
possible  that  the  expense  of  making  separate  estimates  for  individual 
tracts  may  be  greater  than  the  benefits  arising  from  such  a  procedure. 

DEPRECIATION 

The  Treasury  Department  has  issued  many  suggestions  pertaining 
to  depreciation  of  physical  property.  Individual  companies  may  apply 
different  rates  of  depreciation  on  equipment  of  a  similar  nature  if  the 
rates  are  derived  from  reliable  records  kept  by  the  respective  companies. 
It  is  specifically  stated  in  the  regulations  that  each  claim  for  depreciation 
must  show  facts  upon  which  such  claim  is  based.  Special  claims  receive 
special  consideration. 

Depreciation  deductions  are  to  be  charged  to  a  reserve  fund,  and  are 
in  addition  to  any  regular  charge  for  repairs  and  operating  maintenance. 
For  the  general  equipment  of  a  producing  property,  depreciation  may  be 
charged  at  the  same  rate  as  depletion  because  the  general  well  equipment 
is  serviceable  only  as  long  as  the  life  of  the  wells.  This  method  makes  a 
simple  and  consistent  form  for  such  depreciation  charges. 

The  summary  of  the  suggestions  in  Table  1  is  given  as  a  convenient 
method  of  reference,  and  is  taken  from  the  Treasury  Department  Manual 
for  the  Oil  and  Gas  Industry  (see  p.  1718). 

OTHER  ALLOWANCES 

Development  costs,  except  the  cost  of  physical  property,  may  be 
deducted  as  an  expense  in  the  year  in  which  they  are  paid  out  or,  at  the 
option  of  the  taxpayer,  may  be  charged  to  capital  returnable  to  the  sev- 
eral allowable  deductions.  Election  once  made  under  this  option  is  final 
and  will  control  the  returns  for  all  subsequent  years. 

Cost  of  development  comprises  all  payments  made  for  and  incident 
to  the  drilling  of  wells,  such  as  cost  of: 

Physical  property,  geological  and  other  surveys  made  subsequent  to 
acquisition,  roads,  water  supplies,  hauling,  wages,  drilling,  shooting, 
overhead  charges  (incident  to  drilling  of  wells),  fuel  and  all  other  similar 
expenditures. 

Both  cost  of  property  and  cost  of  development,  in  so  far  as  they  have 
not  been  decreased  by  allowable  deductions,  are  chargeable  to  capital 
sum  and  are  returnable  through  the  several  allowable  deductions.  Struc- 
tures and  equipment  may  also  be  included  in  capital  assets  and  are 
returnable  through  depreciation.  In  the  case  of  revaluations  as  of  Mar. 
1, 1913,  or  within  30  days  of  a  discovery  by  the  taxpayer  made  subsequent 
to  Feb.  28,  1913,  the  value  thus  established  plus  subsequent  costs  not 
otherwise  deducted  becomes  the  total  of  capital  sum.  This  revaluation, 
however,  does  not  affect  the  invested  capital,  as  previously  noted. 


388  APPLICATION   OF  TAXATION  REGULATIONS 

TABLE  1. — Summary  of  Suggestions  from  Treasury  Department  Manual 


Class 

No. 

Refer- 
ence 
Page 

Useful 
Life 
Years 

Annual    De- 
preciation, 
Per  Cent. 

A 

1 

57 

Drilling  equipment 

4 

40-25-15-10 

? 

57 

Wells  

3 

57 

Dehydratore 

Electric  

5 

20 

Pipe  and  tanks 

2 

50 

4 

58 

Tanks 
Steel  5000-55,000  bbl 

20 

5 

2500-5000  bbl  

12 

8U 

Galvanized-iron  500-2500  bbl 

12 

o  IX 

Less  than  500  bbl.  . 

8 

12/4 

Wood     .  . 

5 

20 

A 

4 

58 

Movable  tanks  

Galvanized-iron  500-2500  bbl 

g 

11  L^ 

Less  than  500  bbl  

6 

16K 

Water  tanks 
500-2500  bbl  

8 

12  J4 

Less  than  500  bbl 

5 

20 

5 

58 

Tools 

3 

33  LZ 

6 

58 

Transportation  equipment 

3 

33  K 

7 

58 

Water  plants  

10 

10 

s 

58 

Electric*  equipment 

10 

10 

9 

59 

Machine  shops  

7 

14 

10 

59 

Buildings 
Small  wood 

10 

10 

"Frame  structure 

15 

fi  4Z 

* 

Corrugated-iron  siding  

6 

16  H 

Concrete 

25 

4 

Brick 

25 

4 

Steel  

25 

4 

B 

1 

59 

Pipe  lines 
Mains  over  6  in  diameter 

20 

414 

Mains  under  6  in.  diameter  

16 

l« 

Gathering  lines 

10 

9 

Less  10  per  cent,  salvage 
Pump  stations  .                        .    . 

10 

10 

c 

60 

Tank  cars 

20 

5 

D 

1 
1 

60 

62 

Refineries 
Class  1.  Located  at  point  assuring  a  long  supply  of  crude 
oil;  or  well-constructed  plants. 
Class  2.  Located  at  points  assuring  supply  of  crude  oil 
for  several  years. 
Class  3.  Skimming  plants  and  small  refineries  of  poor 
construction,  or  located  at  points  where  supply  of 
crude  oil  is  not  assured  for  a  long  period  of  time. 
Sales  or  marketing  equipment 
Tankers    ...               .... 

20 
10 
6 

20 

5 

10 

i«H 

5 

Barges  

5 

20 

Filling  stations 
Class  A.  Ordinary  wood  or  corrugated-steel  construc- 
tion. 
Class  B.  Brick  and  concrete  or  extraordinary  construc- 
tion. 
Distributing  stations  

5 

10 
10 

20 
10 
10 

Tank  wagons 
Motor 

4 

25 

Horse  

6 

16% 

Steel  barrels 

7 

14  M 

Track  and  switches  

8 

12H 

E 

1 
2 

63 

Natural  gas  (utility  companies) 
Drilling  equipment  (see  A—  1) 
Wells  (see  A-2) 
Gas  pipe  lines 
Mains     

12 

8U 

Gathering  lines 

10 

10 

City  lines  

10 

10 

4 

Compressor  stations                         .      .      .  . 

7 

14  £4 

5 

6 

16?i 

6 

Field  stations                        

4 

25 

7 

5 

20 

Considered  as  a  whole  plant            

10 

20 

F 

1 

64 

Natural  gas  gasoline 
Plant,  compression  with  20  per  cent,  salvage  value  
Absorption  plants  with  20  per  cent  salvage  

4 
4 

35-20-15-10 
35-20-15-10 

THOMAS    COX  389 

Operating  Expenses 

Expense  includes  all  amounts  paid  out  (exclusive  of  amounts  paid 
for  physical  property  and  development  charged  to  capital  sum)  incident 
to  the  development  and  operation  of  producing  properties  and  the 
preparation  of  their  product  for  market,  such  as  costs  of  pumping, 
cleaning,  reshooting  (including  cost  of  torpedoes),  gaging,  storing,  treat- 
ing, reducing,  repairs  and  maintenance,  transporting,  refining,  conserving, 
marketing,  overhead  expense,  insurance,  etc.  The  cost  of  repairs  and 
replacements  made  necessary  through  deterioration  of  equipment  may  be 
charged  off  as  expense,  but  if  this  is  done  the  amount  allowed  as  a  de- 
preciation deduction  will  be  reduced.  In  all  cases,  items  of  expense 
must  be  charged  off  as  such  for  the  year  incurred  and  can  neither  be 
deducted  from  the  income  of  subsequent  years  as  expense  nor  added  to 
capital  sum. 

Repairs 

The  cost  of  incidental  repairs  that  neither  materially  add  to  the  value 
of  the  property  nor  appreciably  prolong  its  life,  but  keep  it  in  an  ordinary 
efficient  operating  condition,  may  be  deducted  as  expense,  provided  the 
plant  or  property  account  is  not  increased  by  the  amount  of  such  expendi- 
tures. Repairs  in  the  nature  of  replacements,  to  the  extent  that  they 
arrest  deterioration  and  appreciably  prolong  the  life  of  the  property, 
should  be  charged  against  the  depreciation  reserve. 

Amounts  expended  for  additions  and  betterments  or  for  furniture  and 
fixtures  that  constitute  an  increase  in  capital  assets  or  add  to  their  value 
are  not  a  proper  deduction,  but  such  expenditures  when  capitalized  may 
be  reduced  through  annual  depreciation  deductions. 

Taxes 

Federal  taxes  (except  income,  war-profits,  and  excess-profits  taxes), 
state  and  local  taxes  (except  taxes  assessed  against  local  benefits  of  a 
kind  tending  to  increase  the  value  of  the  property  assessed),  and  taxes 
imposed  by  possessions  of  the  United  States  or  by  foreign  countries 
(except  the  amount  of  income,  war-profits,  and  excess-profits  taxes 
allowed  as  a  credit  against  the  tax)  are  deductible  from  gross  income. 

Postage  is  not  a  tax.  Amounts  paid  to  states  under  secured-debts 
laws  in  order  to  render  securities  tax  exempt  are  deductible.  Automobile 
license  fees  are  ordinarily  taxes. 

Losses 

Losses  sustained  during  the  taxable  year  and  not  compensated  for 
by  insurance  or  otherwise  are  fully  deductible  (except  by  non-resident 


390  APPLICATION    OP  TAXATION   REGULATIONS     . 

aliens)  if:  incurred  in  the  taxpayer's  trade  or  business;  incurred  in  any 
transaction  entered  into  for  profit;  or  arising  from  fires,  storms,  shipwreck, 
or  other  casualty,  or  from  theft. 

They  must  usually  be  evidenced  by  closed  and  completed  transactions. 
In  the  case  of  the  sale  of  assets,  the  loss  will  be  the  difference  between  the 
cost  thereof,  less  depreciation  sustained  since  acquisition,  or  the  value 
as  of  Mar.  1,  1913,  if  acquired  before  that  date,  less  depreciation  since 
sustained,  and  the  price  at  which  they  were  disposed  of. 

When  the  loss  is  claimed  through  the  destruction  of  property  by  fire, 
flood,  or  other  casualty,  the  amount  deductible  will  be  the  difference 
between  the  cost  of  the  property,  or  its  value  as  of  Mar.  1,  1913,  and  the 
salvage  value  thereof,  after  deducting  from  the  cost  or  value  as  of  Mar. 
1,  1913,  the  amount,  if  any,  which  has  been  or  should  have  been  set 
aside  and  deducted  in  the  current  year  and  previous  years  from  gross 
income  on  account  of  depreciation,  and  which  has  not  been  paid  out  in 
making  good  the  depreciation  sustained.  But  the  loss  should  be  reduced 
by  the  amount  of  any  insurance  or  other  compensation  received.  Losses 
in  illegal  transactions  are  not  deductible. 

Losses  of  oil  and  gas  are  of  two  kinds:  Those  that  are  unforeseen  or 
unavoidable,  such  as  losses  sustained  through  fire  or  accident;  and  those 
that  are  anticipated  and  recognized  as  unavoidable  under  operating 
conditions,  such  as  evaporation  of  oil  in  storage,  ordinary  leakage,  re- 
refinery  losses,  etc.  Usually  losses  of  the  latter  class  are  indeterminate 
as  to  amount  and  are  absorbed,  either  implicitly  or  explicitly,  in  current 
operating  expenses  or  in  cost  of  the  oil  or  gas.  Indeterminate  losses 
may  be  deducted  from  gross  income. 

Compensation  for  Personal  Services 

Among  the  ordinary  anu  necessary  expenses  paid  or  incurred  in 
carrying  on  any  trade  or  business  may  be  included  a  reasonable  allowance 
for  salaries  or  other  compensation  for  personal  services  actually  rendered. 
The  test  of  deducibility  in  the  case  of  compensation  payments  is  whether 
they  are  reasonable  and  are  in  fact  payments  purely  for  services. 

Bonuses  to  Employees 

Gifts  or  bonuses  to  employees  will  constitute  allowable  deductions 
from  gross  income  when  such  payments  are  made  in  good  faith  and  as 
additional  compensation  for  the  services  actually  rendered  by  the  em- 
ployees, provided  such  payments,  when  added  to  the  stipulated  salaries, 
do  not  exceed  a  reasonable  compensation  for  the  services  rendered. 

Donations  to  employees  and  others,  which  do  not  have  in  them  the 
element  of  compensation  or  are  in  excess  of  reasonable  compensation  for 
services,  are  considered  gratuities  and  are  not  deductible  from  gross 
income. 


THOMAS   COX  391 

Damages 

Any  amount  paid  pursuant  to  a  judgment  or  otherwise  on  account  of 
damages  for  personal  injuries,  patent  infringements,  or  otherwise,  is 
deductible  from  gross  income  when  the  claim  is  liquidated  or  put  in 
judgment  or  actually  paid,  less  any  amount  of  such  damages  as  may  have 
been  compensated  for  by  insurance  or  otherwise. 

If  subsequent  thereto,  however,  a  taxpayer  has  for  the  first  time  as- 
certained the  amount  of  a  loss  sustained  during  a  prior  taxable  year,  and 
not  deducted  from  the  gross  income  therefor,  he  may  render  an  amended 
return  for  such  preceding  taxable  year,  including  such  amount  of  loss 
in  the  deductions  from  gross  income,  and  may  file  a  claim  for  refund  for 
the  excess  tax  paid  by  reason  of  the  failure  to  deduct  such  loss  in  the 
original  return.  Provided,  that  no  such  credit  or  refund  shall  be  allowed 
or  made  after  five  years  from  the  date  when  the  return  was  due,  unless 
before  the  expiration  of  such  five  years  a  claim  therefor  is  filed  by  the 
taxpayer. 

Abandoned  Wells 

When  wells  collapse,  become  wet  or  otherwise  unprofitable  producers, 
and  are  abandoned,  the  cost  of  such  abandonment  is  chargeable  to 
current  operations.  Usually  the  value  of  the  recovered  material  is 
credited  to  its  investment  cost  and  the  difference,  not  already  depleted, 
is  deductible  as  being  fully  depleted. 

In  general,  the  deductions  from  gross  income  allowed  corporations 
are  the  same  as  allowed  individuals,  except  that  corporations  may  deduct 
dividends  received  from  other  corporations  subject  to  the  tax  and  may 
not  deduct  charitable  contributions. 

ITEMS  NOT  DEDUCTIBLE 

Donations  to  employees  or  others  that  are  not  compensation  or  are  in 
excess  of  reasonable  compensation  for  services  are  considered  gifts  and 
are  not  deducted  from  gross  income. 


Losses  in  illegal  transactions  are  not  deductible. 

Losses  of  oil  and  gas  are  of  two  kinds:  (a)  unforeseen  or  unavoid- 
able, as  through  fire  or  accident;  (6)  anticipated  and  recognized  as  un- 
avoidable under  operating  conditions,  as  evaporation,  leakage,  refinery 
losses,  etc.  Usually  the  latter  are  indeterminate  as  to  amount  and  are 
absorbed  either  implicitly  or  explicitly  in  current  operating  expenses  or 
in  cost  of  oil^or  gas.  Indeterminate  losses  may  not  be  deducted  from 
gross  income. 

Accrued  Deductions  not  Charged  in  Prior  Years 
The  expenses,  liabilities,  or  deficit  of  one  year  cannot  be  used  to 
reduce  the  income  of  a  subsequent  year.    A  person  making  returns  on 


392  APPLICATION   OF   TAXATION   REGULATIONS 

an  accrued  basis  has  the  right  to  deduct  all  authorized  allowances,  whe- 
ther paid  in  cash  or  set  up  as  a  liability;  it  follows  that  if  he  does  not 
within  any  year  pay  or  accrue  certain  of  his  expenses,  interest,  taxes  or 
other  charges,  and  makes  no  deduction  therefor,  he  cannot  deduct  from 
the  income  of  the  next  or  any  subsequent  year  any  amounts  then  paid  in 
liquidation  of  the  previous  year's  liabilities.  A  loss  from  theft  or  embez- 
zlement occurring  in  one  year  and  discovered  in  another  is  deductible 
only  for  the  year  of  its  occurrence. 

Depletion  for  Past  Years 

Where  under  the  Act  of  Oct.  3,  1913,  or  of  Sept.  8,  1916,  a  taxpayer 
has  not  been  allowed  to  make  a  deduction  for  the  full  amount  of  his  de- 
pletion, the  amount  of  such  deficiency  cannot  be  carried  forward  and 
deducted  in  any  later  year.  Depletion  attaches  to  each  unit  of  mineral 
or  other  property  removed,  and  a  taxpayer  should  make  proper  provision 
therefor  in  computing  his  net  income.  Under  the  Revenue  Act  of 
1918,  the  amount  recoverable  through  depletion  will  be  the  cost,  or  the 
value  as  of  Mar.  I,  1913,  or  within  30  days  of  the  date  of  discovery,  as  the 
case  may  be,  less  proper  allowance  for  the  mineral  or  other  property 
removed  prior  to  Jan.  1,  1918. 

RESUME 

The  foregoing  generally  embraces  a  resume*  of  the  Regulations  and 
methods  of  applying  the  valuation,  and  also  the  depletion,  depreciation, 
amortization,  and  other  deductions  from  gross  income,  of  gas  and  oil 
properties,  and  are  either  copied  or  briefly  condensed  from  the  Treasury 
Department  Regulations  45.  In  the  general  application  of  these,  the 
taxpayer  will,  through  his  proper  books  of  accounts,  record  all  trans- 
actions of  capital,  assets,  reserves  for  depletion,  depreciation,  or  amorti- 
zation and  other  deductions,  also  distributions  of  investments  to  the 
various  facilities  and  cost  of  all  buildings  and  equipment  that  will  fully 
reflect  the  business  conditions.  In  order  to  set  up  the  proper  depletion 
and  depreciation  deductions  from  gross  income,  it  is  necessary  that  an 
investment  be  set  up  on  each  lease  or  property. 

RECORDS  OP  PRODUCTION  AND  ESTIMATED  RECOVERABLE  OIL 

Individual  small  tracts  can  be  more  readily  made  up  than  for  very 
large  ones;  in  fact,  for  small  properties  computation  by  well  areas  make 
a  desirable  and  complete  record. 

Production  records  should  be  kept  by  individual  wells,  if  possible, 
or  as  few  as  are  operated  in  a  group.  Complete  records  for  each  lease  or 
subdivision  are  desirable,  as  copies  of  such  data  are  requested  with  the 
questionnaire.  If  records  of  production  of  individual  wells  were  kept, 
decline  curves  would  be  both  accurate  and  easy  to  produce. 


DISCUSSION  393 

All  gage  tickets  should  be  preserved  for  a  check  of  oil  run  and  balance 
with  production  and  stocks.  These,  too,  record  the  gravity  of  the  oil. 
The  posted  prices  are  recorded  in  the  settlements  for  such  oil. 

Logs  of  wells  should  be  filed  and  preserved  and  a  proper  working  map 
is  necessary  to  show  the  location  of  each  well  and  the  position  of  the 
property  in  relation  to  all  adjoining  leases.  Water  records  should  be 
kept  of  each  well  and  also  time  and  method  of  each  well's  operations; 
also  records  of  suspensions  or  abandonment.  These  data  are  very  useful 
in  connection  with  figuring  depletion  deductions. 

If  the  property  is  large,  the  Geological  Department  defines  the  classes 
of  land  and  directs  the  calculations  of  oil  reserves. 

The  difference  between  invested  capital  and  capital  sum  is  clearly 
defined  in  the  Regulations,  as  also  the  method  for  discovery  revaluations. 
In  practical  operation,  the  chief  items  in  making  up  the  tax  returns  neces- 
sitate that  the  investments  of  each  tract  be  properly  set  up;  that  the 
reserves  be  figured,  methods  submitted  with  records  of  all  productions, 
checking  or  balancing  the  reserves  both  of  past  and  end  of  current  year 
so  that  unit  costs  can  be  readily  and  accurately  obtained. 

The  deductions  for  depletion,  depreciation,  and  others  are  also  readily 
obtained  from  the  proper  method  of  charging,  through  the  books  of 
accounts,  supported  by  the  usual  records  of  production,  shipments,  well 
data,  acreage,  royalties,  and  a  general  systematic  business  routine. 

Generally  the  petroleum  industry  has  adopted  most  of  these  methods, 
and  is  conforming  to  the  new  orders  and  conditions.  The  Regulations 
are  drawn  up  with  clarity  to  aid  operators  in  making  their  returns,  and 
are  worthy  in  their  intent. 

This  paper  is  submitted  through  a  desire  to  arrange  the  laws  and 
rulings  as  a  concise  reference  and  not  with  any  intention  of  presenting 
anything  new. 

Acknowledgment  is  made  to  Mr.  F.  J.  Hoenigmann  for  assistance 
and  aid  in  compiling  these  pages. 

DISCUSSION 

RALPH  ARNOLD,  Los  Angeles,  Calif. — The  subject  of  taxation  must  be 
considered  from  the  standpoint  of  both  the  tax  official  and  the  taxpayer. 
The  needs  of  taxing  jurisdiction  are  paramount  in  communities  depen- 
dent on  mining  or  oil.  When  a  man  says,  "Let  us  use  the  last  production 
tax  or  income  tax,"  he  is  looking  at  the  question  from  his  own  standpoint. 
When  there  is  no  income  or  gross  production,  the  needs  of  the  community 
in  which  the  mine  or  well  is  situated  are  practically  the  same,  so  that 
taxes  must  be  paid  or  the  government  must  fail.  In  such  cases  the 
ad  valorem  system  is  better  fitted  to  conditions. 

Qf  The  question  as  to  whether  this  discourages  development  has  been 
asked.     In  Wisconsin,  where  the  ad  valorem  system  is  used  for  valuing 


394  APPLICATION   OF  TAXATION  REGULATIONS 

iron-ore  properties,  ore  has  been  developed  until  about  two  billion  tons 
are  now  in  sight.  In  Arizona,  also,  this  system  has  not  interfered  with 
the  development  of  new  deposits. 

In  Minnesota,  where  the  dominant  electoral  element  is  agricultural, 
the  taxes  are  based  upon  a  fair  market  value  of  all  properties,  but  the 
assessment  is  33J<$  per  cent,  of  the  value  for  agricultural  property, 
40  per  cent,  for  urban  properties,  and  50  per  cent,  for  mining  properties. 
This  is  a  clear  discrimination  against  mining.  In  Montana  and  Idaho, 
where  the  dominant  influence  is  mining,  the  system  of  taxation  puts  its 
burden  on  the  agricultural  and  other  industries  of  the  state.  In  Cali- 
fornia, the  assessment  in  Orange  County  is  based  on  the  fictitious  value 
established  on  the  production  of  the  previous  year.  It  is  assumed  that 
the  property  will  last  ten  years  and  produce  at  the  same  rate  so  that  value 
is  multiplied  by  ten  to  get  full  value  and  40  per  cent,  of  that  is  taken  as 
the  assessable  value  of  the  property.  If  there  should  be  a  big  produc- 
tion one  year  and  a  small  one  in  the  next,  as  is  often  the  case,  the  taxes 
the  second  year  would  be  out  of  all  proportion  to  one's  ability  to  pay,  and 
have  no  relation  at  all  to  the  taxes  on  the  surrounding  real  estate. 

In  its  report,  the  Mine  Taxation  Subcommittee  of  the  National 
Tax  Association  advocated  the  placing  of  all  taxes,  especially  for  local 
purposes,  on  the  ad  valorem  basis;  that  is,  treating  mines,  oil,  and  gas 
properties  the  same  as  other  classes  of  real  estate. 

The  reason  that  this  question  of  taxation  is  of  great  importance  to 
engineers  and  geologists  is:  If  the  ad  valorem  method  is  adopted, 
and  it  probably  will  be  adopted  in  many  places,  oil  and  gas  properties 
must  be  valued  for  purpose  of  taxation;  that  valuation  will  have  to  be 
done  by  an  engineer,  it  is  not  work  for  the  ordinary  assessor. 

In  the  work  for  the  government,  it  was  necessary  to  employ  engineers 
to  solve  the  tax  problems.  This  question  of  valuation  and  taxation  is 
not  a  subject  for  lawyers,  but  for  engineers.  Just  at  the  present  tkne  the 
lawyers  are  handling  most  of  the  cases,  which  in  many  instances  could 
be  better  done  by  engineers. 

What  is  the  fair  market  value  of  the  property?  The  tendency  now 
is  for  oil  and  mining  companies  to  try  to  base  the  value  on  the 
engineer's  report.  It  is  a  hypothetical  value,  based  on  the  present 
worth  of  the  estimated  amount  of  mineral  in  the  ground.  The  regula- 
tions call  for  consideration  of  a  number  of  factors  in  reaching  this  fair 
valuation.  All  of  these  must  be  taken  into  consideration,  and  I  do  not 
believe  we  are  going  to  arrive  at  a  fair  market  value  by  making  any  one  of 
those  factors  dominant  for  all  localities,  or  for  all  types  of  property. 


VALUATION   FACTORS   OF   CASING-HEAD    GAS  INDUSTRY  395 


Valuation  Factors  of  Casing-head  Gas  Industry 

BY  OLIVER  U.  BRADLEY,*  MUSKOGEE,  OKLA. 

(St.  Louis  Meeting,  September,  1920) 

THE  utilization  of  casing-head  gas  in  the  manufacture  of  casing-head 
gasoline  by  both  the  absorption  and  the  compression  method  is  a  most 
important  factor  in  the  conservation  of  our  natural  resources.  Any 
industry  connected  with  the  oil  business,  in  general,  possesses  particular 
attraction  for  a  large  number  of  people  not  conversant  with  its  basic 
principles,  for  the  reason  that  the  large  fortunes  made  in  the  production 
and  utilization  of  petroleum  and  its  products  have  been  given  undue 
prominence.  The  general  impression  of  the  public  that  enormous  profits 
are  to  be  realized  in  the  casing-head  gas  industry  with  minimum  expendi- 
tures of  both  capital  and  effort  has,  in  a  large  measure,  accounted  for 
the  phenomenal  expansion  of  the  industry  in  recent  years  and,  likewise, 
has  resulted  in  many  mistakes  and  loss  of  investment  funds.  It  is  true 
that  many  installations  have  been  very  profitable,  but  such  instances  are 
always  the  result  of  careful  planning,  experienced  judgment  and  con- 
servative estimates. 

The  inception  and  subsequent  activity  in  the  manufacture  of  casing- 
head  gasoline,  enabling  the  business  to  assume  an  important  position  in 
the  petroleum  industry,  are  of  comparatively  recent  origin,  as  its  greatest 
growth,  particularly  in  Oklahoma,  occurred  during  the  years  1917  and 
1918.  Much  information  must  yet  be  secured  and  systematized  con- 
cerning the  methods  of  manufacture  of  gasoline  from  high-yield  casing- 
head  gas,  and  a  large  field  is  still  open  for  the  application  of  accumulated 
experience  and  good  engineering  practice  in  devising  better  methods  of 
extracting  gasoline  from  casing-head  gas  of  the  poorer  grades. 

The  absorption  process  is  coming  into  general  use  as  a  most  efficient 
system  of  treating  casing-head  gas,  and  even  so-called  dry  gas.  In  fact, 
there  is  a  decided  tendency  toward  the  universal  adoption  of  the  absorp- 
tion process  as  against  compression  methods.  However,  a  general  dis- 
cussion of  the  relative  merits  of  these  two  systems  is  not  within  the  scope 
of  ^his  article. 

A  few  of  the  facts  that  must  be  given  consideration  in  arriving  at  a 
fair  and  ^impartial  estimate  of  the  actual  investment  value  of  the  casing- 
head  gas  business  are  the  quantity  of  gas  available,  the  quality  and 

*  United  States  Oil  and  Gas  Inspector. 


396  VALUATION   FACTOKS   OF   CASING-HEAD   GAS   INDUSTRY 

composition  of  the  gas,  accessibility  of  plant  to  railroads  and  water  sup- 
ply, efficiency  of  operation  of  oil  leases  connected  to  plants,  plant  effi- 
ciency, estimates  of  production  and  marketing  costs,  contract  for  purchase 
of  gas,  and  market  price  of  casing-head  gas. 

QUANTITY  OF  GAS  AVAILABLE 

The  most  important  factors  are  the  quantity  of  casing-head  gas 
available  and  the  conditions  that  will  have  a  material  bearing  on  its 
future  supply,  such  as  location  of  field,  depth  of  oil  wells,  initial  rock 
pressure,  thickness  and  porosity  of  oil  sands,  relative  position  of  oil  and 
gas  strata  in  the  sand,  grade  of  oil,  life  of  oil  wells,  location  and  rapidity 
of  water  infiltration,  vacuum  carried,  and  regularity  of  its  application. 
More  mistakes  have  been  made  in  the  estimation  of  the  available  supply 
of  gas  than  in  any  other  feature  of  the  business.  It  is  at  once  appreci- 
ated that  as  close  a  determination  as  possible  of  the  marketable  quantity 
of  casing  head  gas  is  of  extreme  importance.  When  volume  tests  are 
made,  it  should  be  remembered  that  orifice  tests  of  built-up  pressure  of 
casing-head  gas  on  individual  wells  do  not  necessarily  indicate  the  per- 
formance of  these  wells  under  vacuum  conditions.  The  application  of 
the  vacuum  frequently  increases  the  volume  of  both  oil  and  casing-head 
gas  temporarily,  but  the  effects  of  the  continuous  pperation  of  wells 
under  a  vacuum  cannot  be  clearly  defined,  as  it  is  an  open  question  as 
to  when  and  under  what  conditions  a  vacuum  should  be  applied  to  oil 
wells  in  order  to  produce  the  maximum  extraction  of  both  oil  and  casing- 
head  gas. 

The  exploitation  of  casing-head  gas  is  quite  different  from  ordinary 
mining  operations,  as  available  sources  of  supply  are  not  susceptible  to 
exact  measurements,  like  ore  in  a  mine,  for  example,  which  may  be 
developed  by  shafts  and  drifts,  blocked  out  by  raises  and  winzes,  sampled 
and  assayed,  and  the  mineral  content  closely  estimated.  Casing-head 
gas,  technically  speaking,  is  not  in  place,  cannot  be  stored,  and,  therefore, 
must  be  treated  and  disposed  of  at  once  after  being  brought  to  the  sur- 
face. Many  casing-head  gasoline  plants  have  been  designed  and  erected 
for  the  treatment  of  a  certain  estimated  quantity  of  gas,  which  after  two 
or  three  months  have  found  that  the  supply  of  gas  has  decreased  more 
than  50  per  cent.,  necessitating  the  dismantling  and  removal  of  several 
units  of  the  equipment,  or  having  on  hand  surplus  machinery,  which  im- 
poses a  considerable  handicap  on  the  profitable  operation  of  the  business. 
In  the  case  of  many  plants  in  Oklahoma,  if  conservative  engineering 
estimates  had  been  made  at  the  beginning  of  operations,  a  smaller  plant 
would  have  been  installed  and  additions  made  thereto,  in  case  the  supply 
of  gas  justified  them.  In  this  way,  the  equipment  could  have  been 


OLIVER   U.   BRADLEY 


397 


enlarged  to  meet  the  requirements  of  the  gas  supply  instead  of  reversing 
the  process. 

The  location  of  oil  leases,  with  reference  to  the  general  producing 
area  of  the  pool,  is  important,  as  investigation  has  shown  that  when 
leases  are  located  on  the  edge  of  the  pool  the  casing-head  gas  frequently 
fails  to  maintain  its  usual  volume,  and  its  richness  is  much  less  than  that 
from  wells  in  the  main  or  central  portion  of  the  field.  Consideration 
should  also  be  given  to  underground  conditions  in  estimating  the  possi- 
bilities of  the  supply  of  casing-head  gas. 

QUALITY  AND  COMPOSITION  OP  GAS 

A  chemical  analysis  of  the  gas  should  be  made  in  order  to  determine 
its  actual  physical  characteristics,  as  a  basis  for  applying  a  method  that 
will  obtain  a  maximum  yield  of  casing-head  gasoline.  Furthermore,  a 
practical  field  test  should  always  be  made,  so  as  to  secure  dependable 
information  regarding  the  results  that  may  reasonably  be  expected  in 
the  operation  of  a  plant.  A  demonstration  of  the  desirability,  as  well 
as  the  necessity,  of  applying  both  chemical  and  practical  tests  to  casing- 
head  gas,  is  clearly  shown  in  the  accompanying  data,  giving  percentage 
loss  due  to  evaporation  in  conducting  tests  to  determine  its  correct 
productivity. 


No. 
of 
Test 

Cubic 
Feet 
Used 

Gasoline  Un- 
weathered, 
Cubic  Centi- 
meters 

Gasoline 
Weathered, 
Cubic  Centi- 
meters 

Cubic  Centi- 
meters 
Lost 

Percentage  of 
Evaporation 

Productivity 
per  1000 
Cu.  Ft. 

1 

200 

2,985 

1,960 

1,025 

34.0 

2.59 

2 

200 

3,830 

1,960 

1,870 

48.8 

2.58 

3 

200 

640 

635 

5 

0.9 

0.83 

4 

200 

2,475 

2,070 

405 

16.3 

2.73 

5 

200 

2,405 

2,040 

365 

15.1 

2.69 

6 

167 

1,345 

1,165 

180 

13.4 

1.84 

These  tests  were  all  made  from  casing-head  gas  from  the  Bartlesville 
sand  in  the  Gushing  Field  and  illustrate  the  variability  in  the  composition 
of  such  gas,  the  higher  fractions  sometimes  predominating  and  some- 
times, the  lower. 

Conditions  that  may  produce  a  considerable  variation  in  the  results 
of  tests  may  be  summarized  as  follows:  (1)  The  time  of  the  year  taken, 
as  climatic  conditions  and  temperature  have  a  bearing  on  the  results. 
(2)  Conditions  on  the  lease,  such  as  wells  on  the  pump  or  off,  cleaning 
out  wells,  and  other  lease  work.  (3)  Point  of  sampling  the  gas  and  con- 
ditions under  which  the  sample  is  taken.  (4)  Improper  design  of  ma- 
chine, such  as  lack  of  cooling  surface,  inefficient  compression,  faulty 


398  VALUATION   FACTORS   OP   CASING-HEAD   GAS  INDUSTRY 

manipulation,  poor  connections,  and  defects  in  mechanical  equipment 
designed  to  make  these  tests.  (5)  Natural  error  creeping  in  when  small 
quantities  of  gas  are  tested,  together  with  incorrect  meters.  (6)  Ex- 
cessive evaporation  in  open-air  field  tests. 

Because  of  the  presence  of  one  or  more  of  these  conditions,  the  results 
of  field  tests  are  frequently  too  high  or  too  low  and,  in  calculating  the 
value  of  the  gas,  proper  allowances  should  be  made  after  a  survey  of  all 
the  facts.  If  careful  attention  is  given  to  the  chemical  analysis  of  the 
gas  and  an  effort  is  made  to  get  a  practical  field  test  under  as  nearly  as 
normal  conditions  as  possible,  the  chances  of  error  in  figuring  commercial 
yields  are  greatly  reduced. 

ACCESSIBILITY  OF  PLANT  TO  RAILROADS  AND  WATER  SUPPLY 

Plants  are  sometimes  located  unfavorably  with  regard  to  supply  of 
casing-head  gas.  It  is  frequently  a  debatable  question  as  to  whether 
the  plant  should  be  located  close  to  railroad  facilities,  with  the  supply  of 
gas  several  miles  away,  or  close  to  the  supply,  with  railroad  facilities 
several  miles  distant.  The  general  factors  relative  to  loading  losses,  cost 
of  upkeep  of  field  lines,  and  general  efficiency  of  plant  operations  should 
be  considered  in  selecting  the  location  of  a  plant.  Furthermore,  a  de- 
pendable water  supply  is  always  important.  Numerous  plants  have 
been  located  where  the  initial  expense  of  installing  a  suitable  and  ade- 
quate water  supply  and  its  subsequent  maintenance  have  been  excessive, 
thus  imposing  a  heavy  charge  on  the  future  profits  of  the  business. 

EFFICIENCY  OF  OPERATION  OF  OIL  LEASES  CONNECTED  TO  PLANTS 

Serious  friction  may  often  arise  between  the  operator  of  an  oil  lease 
and  the  manufacturer  of  the  casing-head  gasoline.  This  contingency  is 
of  particular  importance,  though  it  is  frequently  given  no  attention, 
because  the  close  relationship  between  the  production  of  oil  and  casing- 
head  gas  is  not  fully  appreciated.  Considerable  inroads  on  the  profits 
of  a  casing-head  gasoline  plant  may  be  made  by  undue  irregularities  in 
the  operation  of  oil  leases,  such  as  disconnecting  wells  at  inopportune 
times,  cleaning  out  same,  admission  of  air  into  lines  through  leaking 
stuffingboxes  and  defective  lead  lines.  Many  difficulties  of  this  sort 
may  be  eliminated  by  the  incorporation  of  certain  provisions  in  casing- 
head  contracts.  Practically  all  of  the  larger  companies  operate  their 
own  casing-head  gasoline  plants,  or  this  work  is  done  by  closely  affiliated 
or  subsidiary  companies,  which  is  far  more  satisfactory  from  the  stand- 
point of  efficiency,  as  there  will  be  close  cooperation  between  the  oil- 
producing  department  and  the  casing-head  gasoline  division. 


OLIVER  U.  BRADLEY  399 

PLANT  EFFICIENCY 

There  are  many  methods  of  cooling  the  gas  and  its  treatment  under 
varying  pressures;  also,  many  systems  of  blending  are  in  use,  all  of  which 
have  a  material  bearing  on  results.  A  resume*  of  the  numerous  practices 
will  not  be  given  at  this  time.  However,  casing-head  gasoline  manu- 
facturers should  be  willing  to  cooperate  in  comparing  the  various  methods 
employed,  to  the  extent  of  giving  independent  investigators  as  much 
information  as  possible,  as  the  collection  of  reliable  data  on  the  efficiency 
of  different  methods  of  handling  the  various  grades  of  gas  would  benefit 
the  entire  industry  and  need  not  necessarily  make  public  the  particular 
trade  secret  of  any  company.  Under  the  most  careful  management, 
there  will  still  remain  considerable  variations  in  plant  operation,  and 
sometimes  these  differences  will  result  in  changes  of  production  ranging 
from  15  to  20  per  cent,  during  any  one  month. 

Some  of  the  causes,  not  associated  with  the  efficiency  of  plant  opera- 
tion, that  will  produce  substantial  changes  in  monthly  productions  of 
plants  are  as  follows: 

1.  Climatic  conditions.     An  examination  of  the  records  of  monthly 
production  of  casing-head  gasoline  plants  will  show  changes  correspond- 
ing to  the  seasons  of  the  year,  the  production  in  the  spring  and  fall 
months  usually  being  greater  than  that  of  the  summer  and  winter 
months. 

2.  Frequently,  one  or  two  of  the  wells  will  produce  a  different  quality 
of  gas,  when  considered  in  connection  with  its  gasoline  productivity.     If 
the  pressure  on  one  well  should  be  greater  than  on  others,  it  will  naturally 
force  proportionately  more  lean  gas  into  the  plant.     This  will  often  result 
in  a  great  difference  in  the  daily  production;  on  some  days,  this  high 
pressure  will  put  a  greater  quantity  of  gas  into  the  plant  than  on  others. 
The  mixture  of  lean  gases  with  the  regular  gas  coming  into  the  plant 
will  reduce  the  productivity  of  the  entire  volume  of  gas  in  a  considerably 
larger  ratio  than  would  be  revealed  if  a  test  were  made  of  the  individual 
productivities  and  an  average  taken.     It  has  been  found  necessary,  in 
many  plants,  to  cut  out  these  lean  wells  in  order  to  secure  a  reasonable 
degree  of  uniformity  in  the  average  daily  production. 

3.  It  is  necessary,  in  the  operation  of  casing-head  gasoline  plants, 
to  guard   against  excessive  amounts  of  air  in  the  lines.     Daily  tests 
should  be  made  of  the  gas  mixture  entering  the  plant  and  the  presence  of 
excessive  amounts  of  air  should  be  investigated  and  faulty  conditions 
remedied.    Air  not  only  has  a  direct  bearing  on  the  output  of  the  plant 
but  is  a  source  of  considerable  danger  from  explosion,  when  it  reaches  a 
high  percentage  in  the  mixture. 

The  varying  monthly  results  of  plant  operation  may  be  shown  by 
the  following  tabulation: 


400  VALUATION   FACTORS   OF   CASING-HEAD    GAS   INDUSTRY 


MONTH 
April 

TOTAL 
GAS  CONSUMED 
CUBIC  FEET 

8  727  000 

TOTAL 
CONDBNSATE 
PBODUCED 
GALLONS 

30034 

May.. 

9,106,000 

29382 

June  

9  389  000 

18630 

July.. 

9.877,000 

20.741 

GALLONS 

PER  1000 

CUBIC 

FEET 

3.44 
3.23 
1.98 
2.10 


ESTIMATES  OF  PRODUCTION  AND  MARKETING  COSTS 

Careful  estimates  should  be  made  of  the  cost  of  labor  and  supplies, 
superintendence,  insurance,  taxes,  yearly  depletion  of  gas  supply,  depre- 
ciation of  equipment,  the  unavoidable  shipping  losses,  and  the  general 
hazards  of  the  business,  such  as  inability  to  find  a  ready  market  for  the 
product,  due  to  different  specifications  of  purchasers  as  to  gravity  and 
blending  material. 

In  reality,  the  marketing  factor  frequently  becomes  a  question  of 
vital  concern.  Most  manufacturers  of  casing-head  gasoline  must  now 
supply  their  own  cars,  specially  designed  at  considerable  expense,  not 
only  in  order  to  comply  with  the  Federal  shipping  regulations  but  to 
avoid  excessive  evaporation  losses  and  leakage. 

CONTRACTS  FOR  PURCHASE  OF  GAS 

Contracts  for  the  purchase  of  casing-head  gas  have  gone  through  the 
various  stages  of  development,  or  evolution,  corresponding  rather  closely 
to  the  expansion  of  the  industry.  In  a  general  way,  such  contracts  may 
be  divided  into  several  distinct  classes,  viz.: 

(a)  The  flat-rate  contract  in  which  there  is  a  specified  fixed  rate  per 
thousand  cubic  feet  for  the  gas,  extending  over  a  period  coinciding  with 
the  terms  of  the  lease.  These  flat  rates  were  made  in  the  infancy  of  the 
industry  and,  compared  with  present  conditions,  are  extremely  low,  as 
most  of  the  instruments  drawn  for  the  purchase  of  casing-head  gas  in 
the  early  days  show  a  price  ranging  from  3  to  5  cents  per  thousand 
cubic  feet. 

(6)  Sliding-scale  rate  in  which  a  certain  price  is  specified  for  the  gas, 
based  on  the  Chicago  tank-wagon  price  for  casing-head  gasoline,  or 
f.o.b.  loading  rack  price  at  plant,  or  a  designated  local  market;  that  is, 
3  cents  per  thousand  cubic  feet  for  the  gas  when  the  price  of  gasoline  is 
10  cents  per  thousand  cubic  feet,  with  %  cent  increase  in  the  price  per 
thousand  cubic  feet  for  the  gas  for  every  1  cent  increase  in  the  price  of 
gasoline.  These  sliding-scale  contracts  range  from  3  cents  on  10-cent 
gasoline  to  8  cents  on  12-cent  gasoline,  with  the  percentage  increase 
feature.  It  will  be  noted  that  no  mention  is  made  of  the  productivity 
of  the  casing-head  gas. 


OLIVER  U.   BRADLEY  401 

(c)  A  fixed  percentage  of  the  gross  proceeds  derived  from  the  sale  of 
casing-head  gasoline  produced.     Contracts  of  this  character,  varying 
from  25  to  50  per  cent,  of  the  gross  proceeds  are  considered  fair,  as  they 
show  exactly  what  the  plant  produces  and  the  settlement  for  the  gas  is 
made  on  such  basis.     Provisions  are  frequently  incorporated  in  these 
contracts,  charging  up  the  proportionate  cost  of  the  blend  and  its  trans- 
portation against  the  seller  of  the  gas,  particularly  if  the  percentage  of 
gross  proceeds  is  above  40  per  cent.    Some  difficulty  is  encountered,  at 
times,  in  making  settlements  with  royalty  owners  on  the  basis  of  plant 
production,  but  from  the  standpoint  of  the  lessee,  who  usually  owns  a 
group  of  leases,  the  contracts  are  equitable. 

(d)  A  test  of  the  productivity  of  the  gas  and  the  Chicago  tank-wagon 
price  per  gallon  for  gasoline.     The  price  of  the  gas  is  determined  by  a 
schedule  showing  the  yields  of  gasoline  from  the  gas  on  a  scale  of  %-gB,}. 
units,  arranged  in  a  horizontal  column,  and  the  Chicago  tank-wagon 
price  of  gasoline,  in  a  vertical  column.     Several  kinds  of  schedules  are 
in  use  and  are  included  in  contracts,  but  the  principle  involved  in  each 
is  the  same;  the  schedule  shown  in  Table  1  was  suggested  to  the  De- 
partment of  the  Interior  by  different  casing-head  gasoline  producers 
and  was  approved  by  that  Department. 

In  contracts  providing  for  a  test  of  the  gas,  it  is  rare  that  any  method 
of  procedure  is  prescribed  for  making  the  same.  The  ordinary  equip- 
ment and  requirements  of  a  field  test  of  the  productivity  of  casing-head 
gas  that  will  give  reasonable  satisfactory  results  may  be  specified  as 
follows : 

1.  A  fairly  dependable  testing  machine  usually  consists  of  a  small 
gasoline-engine  unit,  belted  to  a  compressor,  with  coil  racks,  cooling 
tanks,  accumulator  tanks,  gages,  meters,  pipe  connections  and  necessary 
fittings,  the  entire  equipment  being  portable.     Coil  racks  should  contain 
at  least  18  ft.  (5.49  m.)  of  %-in.  (9.53  mm.)  galvanized-iron  pipe  in  the 
form  of  a  spiral,  and  all  lines  from  the  compressor  to  the  coils  and  from 
the  coils  to  the  accumulator  tank  should  have  a  natural  drain  so  that  all 
condensate  will  move  to  the  accumulator  tank  by  its  own  gravity    The 
testing  machine  should  be  placed  and  jacked  up  with  this  end  in  view. 

2.  The  compressor  should  make  250  r.p.m.,  in  order  to  do  the  most 
efficient  work. 

3.  The  casing-head  gas  to  be  tested  should  be  taken  from  the  dis- 
charge of  the  vacuum  pump  or  from  the  discharge  of  the  low  side  of  the 
plant  compressor  at  a  pressure  of  4  oz.  at  the  intake  of  the  meter. 

4.  All  leases  connected  to  the  vacuum  pump  should  be  shut  off  except 
the  lease  to  be  tested,  when  such  is  possible,  and  the  main  line  should  be 
given  time  to  clear  itself  of  all  mixed  gases;  or,  a  vacuum-pump  unit 
may  be  installed  on  the  testing  machine,  thus  enabling  a  sample  of  gas 

VOL.  LXV. 26. 


402 


VALUATION   FACTORS   OF   CASING-HEAD   GAS   INDUSTRY 


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OLIVER   U.   BRADLEY  403 

to  be  taken  from  any  point  on  the  field  lines  under  vacuum,  but  such  a 
unit  must  be  operated  efficiently  in  order  to  get  satisfactory  results. 

5.  The  usual  vacuum  should  be  pulled  at  the  time  of  the  test  so  that 
the  quality  of  the  gas  tested  will  be  similar  to  that  ordinarily  utilized  in 
the  plant  in  the  manufacture  of  casing-head  gasoline. 

6.  The  temperature  of  the  cooling  coils  should  be  between  50°  and 
60°  F.  (10°  and  17°  C.). 

7.  Scrubber  tanks  and  lines  at  vacuum  stations  should  be  blown  out 
so  as  to  eliminate  waste  oil  and  all  foreign  matter  before  making  the  test. 

8.  Gasoline  should  be  drawn  from  the  accumulator  tanks  at  atmos- 
pheric pressure.     After  measuring  the  contents,  Baume*  and  temperature 
readings  should  be  taken. 

9.  A  cubic  centimeter  jar  should  be  used  when  weathering;  warm 
water  is  a  satisfactory  medium  for  slowly  raising  the  temperature  of 
gasoline  to  normal,  or  60  degrees. 

10.  The  pressure  on  the  accumulator  tank  at  the  time  the  test  is  run 
should  be  the  same  as  the  pressure  carried  in  the  gasoline  plant.     After 
the  sample  of  gasoline  is  weathered  to  60°  F.,  the  Baume*  reading  should 
be  noted. 

11.  In  starting  the  test,  build  up  the  pressure  of  gas  in  the  machine 
and  the  accumulator  tank  to  300  lb.,  and  note  any  leakage  in  the  line 
or  connections  of  the  machine.     If  no  leaks  appear,  retain  the  pressure 
at  300  lb.  and  blow  off  the  accumulator  tank  until  all  liquid  is  discharged, 
but  do  not  let  the  pressure  go  below  250  lb.,  on  the  gage.     Close  the 
valve  and  start  reading  the  meter  for  the  test. 

12.  If  a  scrubber  tank  is  located  between  the  compressor  and  the 
accumulator,  it  should  be  drained  of  gasoline  upon  the  completion  of  the 
test,  as  some  gasoline  will  always  condense  in  it;  this  gasoline  should  be 
added  to  the  volume  drawn  from  the  accumulator,  in  order  to  get  the 
full  volume  of  casing-head  gasoline  coming  from  the  gas  that  has  been 
metered. 

(e)  Contracts  in  which  the  productivity  of  casing-head  gas  is  deter- 
mined by  the  results  of  plant  production;  that  is,  the  total  number  of 
gallons  of  condensate  produced  during  the  month  is  divided  by  the  total 
volume  of  casing-head  gas  utilized,  which  shows  the  average  productivity 
in  gallons  per  thousand  cubic  feet  of  gas.  The  schedule  shown  in 
Table  1,  or  one  similar  to  it,  may  then  be  used  in  determining  the  price 
of  casing-head  gas  per  thousand  cubic  feet. 

(/)  An  ascending  flat  scale  of  prices  on  a  yearly  basis.  For  example, 
15  cents  for  the  first  year,  20  cents  for  the  second,  25  cents  for  the  third, 
and  so  forth,  no  reference  being  made  to  the  productivity  of  the  gas. 

A  casing-head  gas  contract  constitutes  a  vital  part  of  the  investment 
in  the  business  and,  therefore,  the  terms  should  receive  careful  attention. 
The  more  important  items,  such  as  initial  supply  of  gas,  richness,  and 


404  VALUATION    FACTORS   OF   CASING-HEAD   GAS   INDUSTRY 

estimated  percentage  of  yearly  decline  will  certainly  not  be  overlooked, 
but  minor  considerations,  such  as  the  regularity  of  the  vacuum  carried 
on  wells,  upkeep  of  field  lines,  and  return  of  dry  gas  to  the  lease  for 
operating  purposes  frequently  are  not  given  sufficient  consideration. 
Instances  are  numerous  where  a  provision  for  the  return  of  a  certain 
amount  of  dry  gas  for  lease  purposes  has  made  it  necessary  for  the  gaso- 
line manufacturer  to  purchase  dry  gas  and  supply  it  at  considerable  ex- 
pense to  the  operating  company,  in  order  to  fulfill  the  terms  of  the  contract. 

MARKET  PRICE  OF  CASING-HEAD  GASOLINE 

Market  quotations  for  casing-head  gasoline  are  a  controlling  factor 
in  the  profitable  or  unprofitable  aspect  of  the  casing-head  gas  business; 
it  should  be  pointed  out  that  casing-head  gasoline  is  considered  in  a 
different  class  to  straight-run  gasoline.  The  various  methods  of  handling 
this  product — blending  into  different  grades,  requirements  of  shipping 
in  order  to  make  same  acceptable  to  certain  market  demands,  and  the 
commercial  connections  enabling  a  company  to  get  its  output  before  the 
public — are  matters  of  grave  concern  to  producers  of  casing-head  gaso- 
line. In  conclusion,  therefore,  the  general  conditions  in  the  business  make 
it  necessary  to  take  a  long-range  view,  including  an  estimate  of  the  prob- 
able effect  of  future  demands  and  trade  conditions,  as  related  to  possi- 
bilities of  motor-fuel  substitutes,  from  the  standpoint  of  efficiency  and 
cost  of  production. 


MODIFIED   OIL-WELL   DEPLETION   CURVES 


405 


Modified  Oil-well  Depletion  Curves 

BY  ARTHTTR  KNAPP,  M.  E.,  SHREVEPOET,  LA. 

(New  York  Meeting,  February,  1921) 

OIL-WELL  depletion  curves,  to  be  of  value,  should  show  when  a  well 
or  lease  may  no  longer  be  operated  at  a  profit.  The  difference,  at  any 
time,  between  the  total  expenditures  and  the  total  income  of  a  lease  or 
well  may  be  called  the  lease  status.  Plotting  this  lease  status  against 
time  will  give  a  curve  subject  to  more  accurate  and  different  interpreta- 
tions than  the  barrels-time  curves. 

According  to  the  hypothetical  barrels-time  curves  shown  in  Fig.  1, 
well  A,  at  the  end  of  16  mo.,  is  producing  twice  as  much  oil  as  well  B 
and  will  continue  to  produce  for  another  year  whereas  well  B  will  cease 
producing  in  about  6  months. 


DATA  FOB  LEASE  STATUS-TIME  OR  DOLLARS-TIME  CURVE 


Lease  purchased  for  $3000 

No  expenses  chargeable  to  lease  for  3  mo 

Well  A  is  started;  cost  of  drilling  for  month  is  $16,000 

Well  is  completed  at  additional  cost  of  $10,000 

Well  A  is  brought  in  and  flows  10,000  bbl.  first  month  (see 

Fig.  1).     Necessary  to  invest  in  tanks,  boilers,  pipe  lines, 

etc.;  difference  between  expenditures  and  receipts  gives 

profit  for  month  of  $5,000 

Investment  is  small,  cost  of  operating  well  A  is  small,  so 

profits  are  $15,000 

Well  ceases  to  flow  so  there  is  additional  investment  for 

pumping  equipment  and  additional  operating  expense; 

net  earnings  from  6,000  bbl.  of  oil  produced  is  $4,000 

Lease  operation  now  becomes  normal  and  curve  becomes 

smooth  . , 


TIME 
MONTHS 

0 
2 
3 

4 


8 
9 

10 
11 
12 
13 
14 
15 
16 


LEASE 
STATUS 

-$  3,000 

-  3,000 

-  19,000 

-  29,000 


-  24,000 

-  9,000 

-  5,000 

-  500 
2,000 
4,500 
6,000 
7,700 
8,700 
9,000 
9,500 

10,000 


A  hypothetical  lease  status-time,  or  dollars-time,  curve  of  this  lease 
is  shown  in  Fig.  2.  At  zero  time,  the  lease  is  purchased  for  $3000,  which 
is  plotted  below  the  gerg  dollar  line,  All  subsequent  entries  are  plotted 


406 


MODIFIED   OIL-WELL   DEPLETION   CURVES 


below  this  line  until  total  receipts  exceed  the  total  expenditures,  when 
the  curve  crosses  this  line  and  shows  a  credit,  or  profit. 

Fig.  1  shows  that  well  A  made  600  bbl.  during  the  sixteenth  month, 
or  20  bbl.  per  day,  and  it  indicates  that  an  average  daily  production  of 


Bbls 


Well  A 


Well  B 


24 


6  12  18  24  6  12  18 

Months  Months 

FIG.  1. — HYPOTHETICAL  BARBEL-TIME  CURVES. 

18  bbl.  per  day  may  be  expected  during  the  seventeenth  month.  But 
using  this  curve  to  determine  the  probable  profit  leaves  out  of  account 
the  gradual  increase  in  the  operating  cost,  which  occurs  as  the  well 
becomes  older,  due  to  the  increased  water  to  be  handled,  wear  on  ma- 


25000- 

Salvnrfe 

20000. 

' 

/ 

«H 

1 

/ 

1  15000. 

• 

1 

B 

^  

UlQQDO- 

*~* 

,-- 

.  — 

^^  - 

—  — 

—  — 

— 

,.f 

~—             ^~"~~~~~~-^ 

5000 

> 

s 

/" 

^~ 

-^** 

A 

"""  "~  ""  ""••"•^  ^T~^^^-^ 

Dollars 

1 

0 

/ 

/ 

/ 

1- 

ie 

""^^^    "^^^ 

5000  - 

4 

/ 

/ 

X 

\    10000- 

1 

j 

/ 

/ 

£  15000- 

i 

/ 

/ 

£20000- 

\\ 

\ 

/ 

/ 

25000- 
80000- 

\ 

6  12  18  24  30  30 

Months 

FIG.   2. — HYPOTHETICAL  LEASE  STATUS-TIME,   OR  DOLLARS-TIME,   CURVE  OP  LEASE 

CONTAINING  WELL  A. 

chinery,  etc.     So  that  while  the  well  may  be  profitably  operated  for  100 
bbl.  per  day,  it  cannot  be  profitably  operated  for  5  bbl.  per  day. 

According  to  the  hypothetical  lease  status-time  curve,  though  well 
B  was  depleted  more  rapidly  than  well  A,  it  was  the  more  profitable  well 


ARTHUR   KNAPP 


407 


at  the  end  of  the  sixteenth  month.  It  cost  less  to  drill  and  the  difference 
between  income  and  investment  was  greater  after  the  well  was  completed. 
This  curve  had  not  reached  the  apex  at  the  end  of  the  sixteenth  month, 
although  the  well  was  producing  only  one-half  the  quantity  of  oil  pro- 
duced by  well  A  so  that  well  B  could  have  been  profitably  operated  until 
the  seventeenth  or  eighteenth  month.  The  flatter  curve  of  well  B  maybe 


100000 
80000 

GOOOO 


20000 
10000 

5000- 

Dc  liars. 

10000- 


Solvage 


If  Salvage 

-Max.  Probable  Price 
of  Oil 


1  Year  2  Years  3  Years 

FIG.  3. — TYPICAL  CURVE  OF  LONG-LIVED  WELL  FOB  GULF  COAST  FIELD. 

due  to  the  fact  that  the  operating  expenses  were  uniformly  lower  than 
those  of  well  A  because  they  were  shared  by  several  properties,  while  well 
A  was  so  far  from  other  production  as  to  necessitate  its  being  operated 
by  itself.  A  difference  in  the  amount  of  salt  water  handled  would  influ- 
ence the  curve. 


25000- 

20000- 

15000- 

J^OBB  if  rig  t§  renewed  in 

10000- 

-> 

•"' 

. 

/ 

L 

^ 

-1 

Profit  If  rig  is  renewed  ID 

5000- 

1 

/ 

V 

10th  month 

Drill      A 

f 

5000- 

4- 

/ 

10000- 

15000- 

\ 

/ 

„, 

20000- 
25000- 

\ 

/ 

1 

30000- 

2        4       6       8       10      12      14     18      18 

FIG.  4. — DOLLARS-TIME  CURVE. 

As  stated,  these  curves  are  hypothetical.  Few  wells  would  show  a 
profit  for  one  month  and  a  sufficient  loss  the  next  month  to'  warrant 
abandoning  the  well.  In  a  great  many  cases,  the  apex  of  the  curve  is 
flat  and  a  small  profit  will  be  shown  for  a  period  extending  from  several 
months  to  several  years.  In  order  to  show  the  method  to  be  followed, 
the  simplest  case  has  been  taken. 

OTHER  USES  OF  LEASE  STATUS-TIME  CURVES 

Depreciation  of  the  derricks,  pumping  rigs,  and  machinery  do  not 
materially  affect  the  lease  status-time  curves  of  short-lived  wells.  If, 


408 


MODIFIED    OIL-WELL   DEPLETION    CURVES 


however,  the  wells  are  long  lived  the  salvage  value  may  determine  the 
point  at  which  wells  may  be  profitably  pulled.  Fig.  3  shows  a  typical 
curve  of  a  long-lived  well  for  the  Gulf  Coast  field.  This  well  shows  a 
good  profit  up  to  the  end  of  the  second  year.  During  the  third  year 
there  will  be  a  small  profit  but  the  curve  shows  that  the  salvage  value  at 
the  end  of  the  second  year  is  greater  than  the  probable  salvage  value  at 
the  end  of  the  third  year  plus  the  probable  profit  for  the  year.  It  would, 
therefore,  be  more  profitable  to  abandon  the  lease  at  the  end_of  the 
second  year  than  to  operate  during  the  third. 

In  attempting  to  analyze  such  curves  for  as  long  a  period  as  a  year 
account  must  be  taken  of  the  probability  of  a  fluctuation  in  the  price  of 


i 


1  !  , 


I  I 

*      2 


Time 

FIG.  5. 

oil.  Fig.  3  shows  that  even  taking  into  account  the  maximum  probable 
increase  in  the  price  of  oil  the  maximum  profit  from  this  lease  will  be 
obtained  by  pulling  the  wells  at  the  end  of  the  second  year.  If  consider- 
able repairs  are  necessary  this  form  of  curve  is  valuable  for  deciding 
whether  or  not  the  investment  is  warranted. 

The  recovery  value  of  wells  A  and  B  added  to  Fig.  1  show  that  while 
well  'B  showed  a  greater  profit  than  well  A  when  both  reached  the 
apex  of  their  curves,  the  final  profit  from  each  well  was  the  same,  as  the 
salvage  from  well  A  was  greater  than  that  from  well  B. 

In  the  case  of  accidents,  such  as  fire,  it  is  hard  to  determine  whether 
or  not  the  investment  in  new  rigs  and  machinery  will  be  profitable.  With 
the  dollars-time  curve,  as  shown  in  Fig.  4,  this  question  may  be  decided 
with  some  degree  of  accuracy.  If  the  fire  occurred  in  the  tenth  month 


ARTHUR   KNAPP  409 

and  the  renewal  was  estimated  at  $5000,  transposing  the  probable  lease 
status  curve  shows  that  the  additional  investment  is  warranted,  for  the 
apex  of  the  curve  finally  rises  above  the  point  at  which  the  fire  occurred. 
If,  however,  the  fire  occurred  in  the  fourteenth,  the  curve  will  not  rise 
above  the  profit  shown  at  the  time  of  the  accident,  which  means  that  it 
would  not  be  profitable  to  renew  the  machinery. 

LEASES  WITH  MORE  THAN  ONE  WELL 

While  the  majority  of  leases  have  more  than  one  well  and  the  several 
wells  are  not  all  drilled  at  one  time,  this  does  not  affect  the  curve  after 
the  drilling  program  is  complete  and  the  production  is  settled.  While 
drilling  the  second  and  subsequent  wells  the  lease  status  curve  may  run 


10          12          14        16 
Months 

FIG.  6. — LEASE  STATUS-TIME  CURVE  FROM  A  PROPERTY  IN  PINE  ISLAND,  LA., 
DISTRICT.  RECORDS  NOT  AVAILABLE  PREVIOUS  TO  FOURTH  MONTH.  NINE  WELLS 
DRILLED  ON  160-ACRE  LEASE  BETWEEN  FOURTH  AND  NINTH  MONTH.  DECREASE  IN 
PRODUCTION  AND  INCREASE  IN  AMOUNT  OF  SALT  WATER  WAS  SO  RAPID  THAT  FOUR 
MONTHS  AFTER  DRILLING  PROGRAM  WAS  COMPLETE  THE  LEASE  CEASED  TO  BE  PROFIT- 
ABLE WITHOUT  HAVING  PAID  OUT.  AN  INCREASE  IN  PRICE  OP  OIL  IN  FIFTEENTH 
MONTH  SERVED  TO  CHECK  THE  LOSS  BUT  DID  NOT  TURN  IT  INTO  A  PROFIT.  CURVE 
SHOWS  CONCLUSIVELY  THAT  REGARDLESS  OF  AMOUNT  OF  PRODUCTION  OR  AGE  OP 
WELLS,  THE  LEASE  SHOULD  BE  ABANDONED.  INSERT  SHOWS  DEPLETION  CURVE  OP 
LEASE.  PREVIOUS  TO  TWELFTH  MONTH,  NO  GAGE  OF  DAILY  PRODUCTION  COULD  BE 
TAKEN,  AS  WELLS  PRODUCED  INTO  EARTHEN  STORAGE. 

nearly  horizontally,  the  income  from  production  of  the  wells  drilled  off- 
setting the  cost  of  wells  drilling.  When  all  the  wells  on  a  lease  are  pump- 
ing into  the  same  tank  and  all  of  the  wells  have  been  drilled  within  a 
reasonable  length  of  time  of  one  another,  the  depletion  curve  of  the  lease 
is  a  fair  gage  of  the  depletion  of  each  well. 

PROPERTY  VALUATION 

The  value  of  a  property  is  its  salvage  value  plus  its  probable  earnings 
up  to  the  time  it  reached  the  point  of  maximum  profit,  interest,  taxes, 
and  insurance.  If  the  lease  status-time  curves  have  been  properly  and 
accurately  drawn,  the  value  of  any  property  maybe  taken  directly  from  its 
curve.  As  interest,  taxes,  and  insurance  are  constants,  they  do  not  affect 
the  shape  of  the  curve  and  need  not  be  included  for  ordinary  analysis, 


410 


MODIFIED-OIL-WELL  DEPLETION  CURVES 
VARIATIONS  OF  DATA 


Variations  in  the  systems  of  bookkeeping  may  produce  slightly  differ- 
ent curves  but  they  usually  allow  for  the  same  analysis  as  outlined. 
If  interest  and  overhead  are  charged  monthly  to  the  expense  of  the  lease 
they  make  a  more  accurate  curve  but  do  not  affect  the  shape.  If  depre- 
ciation is  charged  off  yearly  against  the  lease,  it  should  be  prorated 
monthly  at  the  end  of  ,the  year  and  the  lease  status  curve  redrawn. 


Lease  operating  at  a  loss  due  to  some 
sudden  change  in  condition 
of  wells  or  lease 


Dollars 


Salvage 


(Accrued  Profit ) 


(Accrued  Loss) 


24  6          8          10         12          14         15         18 

Months 

FIG.  7. — END  OP  A  LEASE  STATUS-TIME  CURVE  is  GIVEN  ABOVE.    IF  CAREFUL 

ATTENTION  HAD  BEEN  PAID  TO  STATUS  OF  LEASE,  IT  WOULD  NOT  HAVE  BEEN  OPERATED 
AT  A^LOSS  FOR  SO  LONG  A  TIME. 


Dollars 


(Accrued  Profit^ 


(Accrued  Loss 


10 


12         14 
Months 


FIG.  8. — A.   LEASE  WAS  BEING  OPERATED  AT  GOOD  PROFIT  UNTIL  SALT  WATER 

BROKE  IN  AND  RUINED  ONE  OF  THE  WELLS. 

B.  ADVANCE  IN  PRICE  OF  OIL  CHANGED  A  SMALL  LOSS  INTO  A  SMALL  PROFIT. 

C.  LEASE  WAS  OPERATED  FOR  NINE  MONTHS  AT  TOTAL  PROFIT  OF  $48.    DEPRECIA- 
TION ON  MACHINERY  WOULD  MORE  THAN  OFFSET  THIS. 

The  easier  way,  provided  the  bookkeeping  system  will  allow,  is  to  charge 
the  total  investment  against  the  lease  and  credit  the  salvage  to  the  lease 
when  the  operation  is  stopped. 

EXAMPLES  FROM  PRACTICE 

The  curves  shown  in  Figs.  6,  7,  and  8  are  taken  from  data  of  actual 
operations.  In  one  case,  the  full  curve  is  given  and  in  the  rest  just 
enough  of  the  curve  is  shown  to  illustrate  the  point  desired.  The  values 
of  the  dollar  ordinate  have  not  been  given,  the  various  curves  having 
been  reduced  to  the  same  size  as  various  scales  on  the  dollar  ordinate 
would  be  confusing. 


DISCUSSION  411 

DISCUSSION 

ROSWELL  H.  JOHNSON,*  Pittsburgh,  Pa. — The  curve  suggested  differs 
from  many  other  curves  in  being  what  might  be  called  synthetic;  it 
shows  in  one  line  the  net  result  of  several  items  to  get  the  result  in  which 
the  executive  is  particularly  interested.  Another  feature  is  that  it  is 
simply  calculated,  so  that  it  can  be  made  cheaply.  If  the  executive 
does  not  care  about  graphs,  the  same  data  in  tabular  form  can  be  a 
guide.  The  graph  should  carry  the  numerical  data  on  the  sheet  for  the 
use  of  the  executive. 

It  would  be  a  mistake  for  the  executive  to  feel  that  all  the  information 
he  needs  is  in  this  one  graph.  He  should  also  watch  graphs  showing  his 
cost  per  well  for  maintenance,  in  order  to  check  the  relative  efficiency 
on  his  leases  and  personnel;  he  should  also  keep  a  graph  on  decline  but 
the  ordinary  decline  curve  is  not  helpful  in  old-age  wells.  The  slope  of 
the  decline  on  an  old-age  well  does  not  show  up  fine  differences  at  all 
easily  so  that  a  graph  showing  the  proportion  of  one  year  to  the  previous 
year  (persistence  factor)  will  show  readily  the  changes  in  his  rate  of 
decline. 

*  Professor  of  Oil  and  Gas  Production,  University  of  Pittsburgh. 


412  BARREL-DAY  VALUES 


Barrel-day  Values 

BY  GLENN  H.  ALVEY  AND  ALDEN  W.  FOSTER,  PITTSBURGH,  PA. 
(New  York  Meeting,  February,  1921) 

THE  measure  of  value  of  an  oil  property  is  approximated  by  the  length 
of  time  it  takes  to  "pay  out;"  viz.,  the  time  required  for  it  to  return  the 
original  investment.  This  time  varies  in  different  fields.  In  the  Appa- 
lachian and  Mid-Continent  fields,  a  good  investment  pays  out  in  about 
four  years;  in  California,  it  requires  a  slightly  longer  time;  and  in  the  Gulf 
field  about  two  years. 

The  two  principal  methods  for  establishing  these  values  are  based 
on  acreage,  as  in  California,  and  on  production,  as  in  the  Appalachian 
field.  The  method  of  establishing  values  based  on  production1  was 
worked  out  in  the  Appalachian  fields  and  approximates  the  value  re- 
markably well  in  some  fields;  but  it  is  a  rule  of  thumb  and  should  be 
used  intelligently.  Briefly,  the  method  is  as  follows:  An  arbitrary  num- 
ber of  dollars  (called  the  barrel-day  price)  multiplied  by  the  number  of 
barrels  of  settled  daily  production  of  the  property  gives  the  value.  In 
its  crudest  application,  the  barrel-day  price  is  determined  by  the  "$10  to 
$0.01"  rule,  which  means  that  the  barrel-day  price  is  one  thousand  times 
the  prevailing  price  of  oil.  For  instance,  with  oil  at  $3.50  per  bbl.  the 
barrel-day  price  would  be  $3500  per  bbl.  This  rule,  however,  is  not 
strictly  applied,  for  the  barrel  price  is  varied  according  to  whether  or 
not  the  wells  "hold  up."  But  when  a  barrel  price  for  a  district  has  been 
fixed  it  is  quite  general  to  raise  or  lower  the  price  with  the  fluctuation  in 
the  price  of  oil;  here  the  "$10  to  $0.01  "rule  is  used  extensively.  However, 
the  prospective  purchaser  takes  into  account  tangible  equipment  upon 
the  property,  the  extent  to  which  the  drilling  program  has  been  carried 
out,  whether  or  not  the  wells  are  "shot"  or  natural,  depth  of  wells,  spacing 
of  wells,  paraffin  trouble,  etc. 

The  basis  of  this  method  is  settled  production.  As  soon  as  production 
is  considered  settled,  a  flat  barrel-day  price  is  generally  applied  to  all 
properties,  no  matter  what  their  age.  If  it  were  possible  to  show  that 
this  flat  rate  was  erroneous  and  that  the  value  of  the  property  depended 
on  the  point  on  the  decline  curve  at  which  the  wells  happened  to  be  (in 
other  words,  their  age),  and  also  on  the  operating  costs,  the  future  price 

1  Acknowledgment  is  due  to  Roswell  H.  Johnson,  at  whose  suggestion  this  problem 
was  undertaken. 


GLENN  H.  ALVEY  AND  ALDEN  W.  FOSTER 


413 


of  oil,  and  the  discounted  value  of  the  dollar,  the  buyer  who  recognized 
these  facts  and  bought  accordingly  (also  observing  depth  and  spacing 
of  wells,  etc.)  would  be  in  an  advantageous  position;  and  the  seller  (al- 
though he  does  not  usually  have  sufficient  data  at  hand  to  make  a  com- 
plete appraisal)  would  be  able  to  know  when  to  sell  his  property  to  the 
best  advantage. 

It  is  the  purpose  of  this  paper  to  show  that  there  is  a  best  time  to  buy 
or  sell  production;  in  other  words,  that  the  value  of  property  varies  with  a 
number  of  complex  factors,  most  of  which  may  be  used  in  making  an  analytic 
appraisal  of  a  property.  To  demonstrate  the  possibility  of  doing  this, 
two  problems  are  presented: 

First. — In  a  given  pool,  one  well  was  brought  in  May  1,  1920, 
one  was  one  year  old  on  that  date,  another  two  years  old,  still  another 


5 

1° 

1 

r 

5    3 
aT 
£    2 

h 
tt 

0    1 

y 

- 

15 

S  14 

S  12 
0  11 

/ 

X 

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A     5 
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x^ 

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• 

0     1    2     3    4     5    0     7     8     9   10   11    12  13  14   15    16               "  0  1  2  34  56  18  910          15          20          25          3C 
Years                                                                                                 Sears 

FIG.  1.  FIG.  2. 

FIG.  1. — BARREL-DAY  VALUES  AND  CURRENT  BARREL-DAY  PRICES  FOR  MAY  1, 1920, 
FOR  AVERAGE  WELLS  OF  DIFFERENT  AGES  IN  CAMERON  DISTRICT,  PA. 

FIG.  2. — BARREL-DAY  VALUES  AND  CURRENT  BARREL-DAY  PRICES,  ASSUMING  THAT 
WELL  CAME  IN  WITH  OIL  AT  $6  PER  BARREL,  FOR  DIFFERENT  YEARS  IN  LIFE  OF 

AVERAGE  WELL  IN  CAMERON  DISTRICT,  PA. 

was  three  years  old,  and  so  on.  Which  of  these  wells  is  it  best  to  buy, 
the  one  that  just  came  in,  one  four  years  old,  or  one  seven  years  old? 

Second. — To  get  the  best  return  of  the  money  invested,  should  a  well 
that  comes  in  on  May  1,  1920,  be  purchased  on  that  date,  or  two  years 
from  that  date,  or  some  years  later? 

For  the  first  problem,  the  barrel-day  value  of  an  average  well  was 
determined  on  the  assumption  that  it  came  in  May  1,  1920;  also,  the 
barrel-day  value  as  of  May  1,  1920  if  the  well  had  come  in  a  year  prior 
to  that  date,  two  years  prior  to  that  date,  and  so  forth,  until  a  sufficient 
number  of  years  prior  to  make  it  ready  for  abandonment  on  May  1, 1920, 
had  been  considered.  These  barrel-day  values  were  plotted  and  curves 
drawn.  Similarly,  for  the  second  problem,  analytical  appraisals  were 


414  BARBEL-DAT  VALUES 

made  for  each  year  in  the  life  of  an  average  well,  assuming  that  the  well 
came  in  May  1,  1920.  That  these  values  are  different  from  those  of  the 
preceding  problem  is  due  to  the  advancing  price  of  oil.  In  the  first  case, 
each  appraisal  starts  with  the  price  on  May  1,  1920;  in  the  second  case 
advanced  prices  of  oil  were  used.  In  working  out  these  appraisals,  the 
following  form  was  used: 

TABLE  1 

NET        PBICB  w  COMPOUND 

VU-AR     YEARLY       PER     GROSS  INCOME    rv>«,™  ™=      NET  YEARLY      DISCOUNT       DISCOUNTED 
BAB    PRODUC-     BAR-        FOR  YEAR  yl^  INCOME  FACTOR  INCOME 

TION         REL  714  PER 

CENT. 

ABC      BXC  =  D        E         D-E=F          G          F  X  G  =  H 

1 
2 
3 
4 


n  (7)  Total 

Economic  limit 
/  =  salvage, 

K  =  compound  discount  factor  for  n  years, 
J  X  K  =  L  =  discounted  salvage, 
/  +  L  =  present  worth, 
M  =  daily  production  at  beginning  of  year, 
L  -5-  M  =  barrel-day  value. 

These  values  were  worked  out  for  the  Cameron  district,  Pennsyl- 
vania, of  the  Appalachian  field,  and  the  Osage  Nation  of  theMid  -Continent 
field.  The  production  data  used  in  the  former  case  were  secured  from  a 
company  operating  in  that  district;  in  the  latter  case,  from  BeaFs  Decline 
Curve.1  An  advancing  price  of  oil  was  predicted;  2  per  cent,  for  the 
Cameron  district  (which  was  chosen  in  order  to  give  a  constant  advance 
up  to  $10  during  the  life  of  the  well),  and  10  per  cent,  for  the  Osage  until 
the  price  reached  $10  for  the  remaining  years  (which  was  taken  so  as  to 
accord  more  closely  with  the  price  predictions  that  are  considered  to  be 
correct  for  the  Mid-Continent  field).  Costs  were  taken  at  $600  per  year 
for  the  Cameron  district  and  $1  per  well  day  for  the  Osage.  A  7J^  per 
cent,  compound  discount  factor  was  used.  The  salvage  value  used  for 
the  Cameron  district  was  $2000,  and  for  the  Osage  $1000  (see  Table  2). 

Fig.  1  shows  the  curve  for  wells  at  different  ages  in  the  Cameron 
district;  the  barrel-day  values  are  plotted  against  the  ages  of  the  wells. 
According  to  this  curve  the  highest  barrel-day  value  is  for  a  well  five 
years  old ;  this,  therefore,  would  be  the  best  well  to  buy  because  the  present 

»  U.  S.  Bureau  of  Mines  Butt.  177,  108. 


GLENN   H.    ALVEY   AND   ALDEN   W.   FOSTER 


415 


worth  of  the  future  production  of  this  well,  compared  to  its  daily  present 
production,  is  the  highest.  The  barrel-day  values  of  older  wells  decrease 
until  those  ages  are  reached  at  which  the  well  is  near  abandonment,  when 
the  barrel-day  values  rise  sharply.  This  is  because  of  the  higher  pres- 
ent worth  of  the  salvage  (the  salvage  value  is  discounted  less  and  less 
with  the  advancing  age  of  the  well).  It  would  be  attractive  to  buy  an 
old  well  on  the  barrel-day  rate  because  one  can  sell  the  salvage  and  make 
a  profit. 

TABLE  2 


DISTRICT 


PRICE  OF  OIL  AS  OF 
MAY  1,  1920 


WELL  COSTS 
PER  YEAR 


COMPOUND 

DISCOUNT 

FACTOR, 

PER  CENT. 


Cameron,  Pa $6.00    with    2    per 

cent,  rise  (yearly) 


Osage,  Okla, 


$3.50  with  10  per 
cent,  rise  up  to  $10 
and  then  a  flat  rate 
of  $10. 


$600.00 


$365.00 


SALVAGE 


$2000.00 


$1000.00 


COMPOUND 
DISCOUNT 

FACTOR  FOR 
SALVAGE. 

PER  CENT. 


Barrel-Day  Value, 
n  Thousands  of  Dollars 

A 

/ 

^ 

N 

/ 

/ 

\ 

J 

\ 

x' 

\ 

1 

| 

I 

1 

0  1  2  3  4  5  6  7  8  9  10   12  14    16 
Years 


J.O 

15 
I14 

•312 

5  u 
sio 

1  9 

a  8 

•3    6 

i! 

£    3 
5    2 

1 

> 

^ 

\ 

•\ 

\ 

: 

\ 

/ 

> 

1 

V 

/ 

\ 

" 

z 

s. 

<~s-" 

r 

/ 

/ 

/ 

/ 

(  ( 

"012S    6     9    12   15   18  21   24  27   30  33  36   39  42  46 

Years 


FIG.  4. 


FIG.  3. 

FIG.  3.  —  BARREL-DAY  VALUES  FOR  AVERAGE  WELLS  OP  DIFFERENT  AGES  IN  EASTERN 
PART  OF  OSAGE  INDIAN  RESERVATION,  OKLA. 

FIG.  4.  —  BARREL-DAY  VALUES  FOR  DIFFERENT  YEARS  IN  LIFE  OF  AVERAGE  WELL  IN 
EASTERN  PART  OF  OsAGE  INDIAN  RESERVATION,  OKLA. 


Fig.  2  shows  the  changes  on  barrel-day  values  for  different  periods 
in  the  life  of  a  single  well  in  the  Cameron  district.  According  to  this 
curve,  the  best  time  to  buy  is  six  years  from  the  date  the  well  was  brought 
in,  for  then  the  well  has  its  highest  barrel-day  value. 

Figs.  3  and  4  are  similar  to  Figs.  1  and  2,  respectively,  but  are 
for  the  Osage  district.  The  most  interesting  fact  is  that  the  highest 
barrel-day  values  come  much  later  than  for  Cameron.  This  is  due  to  a 


416  BARBEL-DAY  VALUES 

flatter  decline  curve  and  a  steeper  predicted  price  curve.  The  significance 
of  this  is  that  no  generalization  can  be  drawn  for  the  best  year  to  buy  that 
will  apply  to  all  pools.  It  must  be  worked  out  for  each  pool  and  the 
year  determined  will  be  influenced  by  the  price  of  oil  predicted  by  the 
appraiser. 

CONCLUSIONS 

The  barrel-day  value  for  settled  production  is  not  flat,  as  is  generally 
supposed,  but  from  completion,  increases  with  the  age  of  a  well  up  to  the 
maximum  and  then  decreases;  it  increases  again  when  the  salvage  value 
becomes  attractive. 

There  is  a  method  by  which  the  age  at  which  a  well  has  the  highest 
barrel-day  value  can  be  determined. 

This  age  varies  with  the  different  pools  and  is  due  to  five  causes:  the 
decline  curve  of  the  pool,  future  price  of  oil,  well  costs,  compound 
discount  factor,  and  salvage  value. 

DISCUSSION 

* 

ROSWELL  H.  JOHNSON,*  Pittsburgh,  Pa. — The  belief  that  one  may 
appraise  on  a  flat  barrel-day  value  is  one  of  the  most  dangerous  blunders 
in  the  oil  business.  It  is  properly  merely  a  method  of  expressing  prices. 
Some  appraisers  start  with  it  as  a  basis  and  then  work  plus  and  minus 
from  it.  Such  a  procedure  is  crude  and  objectionable. 

These  curves  of  Alvey  and  Foster  show  characteristically  three 
stages.  In  the  first  stage  the  decline  rate  is  the  dominant  factor,  and 
throughout  it  the  unit  value  advances;  the  rapid  increase  in  unit  value 
is  the  outstanding  characteristic.  The  one  exception  is  where  we  have 
wells  that  are  very  short-lived,  such  as  some  Ranger  and  Gulf  Coast 
wells,  where  it  is  quite  possible  that  the  second  year  would  show  a  poorer 
value  than  the  first,  because  the  whole  thing  has  been  shortened  and  the 
year  unit  is  too  large  a  unit  for  such  a  curve. 

The  next  stage  is  where  the  cost  is  the  dominant  factor;  the  rate  of 
decline  is  less  weighty  and  the  cost  is  steadily  becoming  a  more  important 
factor. 

The  third  stage  is  dominated  by  the  foreshadowing  of  the  salvage  due 
and  represents  the  final  up  turn  at  the  end.  A  curve,  such  as  is  made 
here,  can  be  constructed  without  salvage  value,  treating  the  salvage 
value  as  a  separate  unit;  but  it  seems  best  to  put  in  the  salvage  value 
consideration. 

In  Table  1  is  the  best  working  formula  for  oil  appraisal  that  has 
yet  appeared  in  literature.  In  column  E,  well  costs  are  handled  by  the 
year,  after  yearly  production  has  been  multiplied  by  the  price  per  barrel. 
That  is  the  place  to  take  out  the  cost,  because  if  taken  earlier  it  will  be 

*  Professor  of  Oil  and  Gas  Production,  University  of  Pittsburgh. 


DISCUSSION  417 

taken  out  on  the  barrel  basis,  which  is  so  variable  as  it  depends  on  pro- 
duction. Costs  then  ought  to  be  taken  out  on  the  basis  of  the  well  cost, 
not  the  barrel  cost.  This  formula  puts  in  discounted  salvage,  which 
feature  has  not  always  been  recognized. 

The  formula  makes  obsolete  the  time-to-pay-out  and  the  acre-yield 
methods,  in  their  usual  forms  except  for  the  most  rapid  work.  Both 
suffer  so  severely  by  their  non-recognition  of  the  time  element  of 
compound  discount,  that  they  are  fallacious.  It  is  surprising  to  note, 
for  instance,  that  in  a  long-lived  curve,  such  as  Salt  Creek,  the  com- 
pound discount,  if  one  takes  it  at  10  per  cent,  cuts  down  the  value  to 
only  45  per  cent  of  the  uncorrected  acre-yield  value.  With  such  an 
enormous  range  as  that,  the  danger  of  acre-yield  methods  is  seen. 

The  time-to-pay-out  methods  are  so  crude,  in  that  they  ignore  the 
shape  of  the  curve  after  the  well  is  paid  out,  that  they  cannot  be  con- 
sidered. Acre-yield  and  time-to-pay-out  methods  can  be  used  for  quick 
appraisal,  however,  if  one  works  a  series  of  annual  analytic  values  and 
uses  these  values  to  set  up  tables  using  various  assumptions. 

Another  feature  of  this  paper  that  demands  attention  is  the  method 
of  predicting  a  price  advance.  It  is  here  taken  on  a  percentage  basis  to  a 
plateau,  and  then  flattened.  This  is  better  than  the  method  of  fixed 
advance  in  cents  per  barrel;  because,  first,  the  price  of  different  grades 
of  crude  do  not  fluctuate  with  fixed  differentials  in  cents,  but  by  percent- 
age of  the  highest  grade  although  these  percentages  are  not  absolutely 
fixed.  For  instance,  all  of  us  have  been  looking  at  these  recent  cuts  in 
prices.  We  noticed  that  Kansas-Oklahoma  oil-  was  cut  50  per  cent., 
and  so  predicted  a  drop  in  Pennsylvania  of  50  per  cent.;  and  we  knew 
before  the  last  cut  that  there  was  another  cut  due,  and  still  another 
is  due. 

Furthermore,  the  theory  of  making  price  advance  based  on  the  fixed 
amount  per  barrel,  would  have  to  be  dependent  on  the  thought  that  as 
the  price  rises  the  demand  is  shortened.  But  in  the  case  of  oil  and  gas  we 
have  some  peculiar  conditions.  There  is  a  nearly  constant  expansion 
of  the  market  for  oil.  We  have  oil  going  into  new  things — the  tractor, 
the  motor  boat,  the  Deisel  engine — so  that  these  larger  needs  postpone 
saturation. 


VOL.  LXV. — 27. 


418       ISOSTATIC  ADJUSTMENTS   IN  THEIR  RELATION  TO   OIL   DOMES 


Isostatic  Adjustments  on  a  Minor  Scale,  in  their 
Relation  to  Oil  Domes* 

BY  M.  ALBERTSON,!  E.  M.,  SHREVBPORT,  LA. 

(New  York  Meeting,  February,  1921) 

AT  Cobalt,  Ontario,  Canada,  a  lake  was  drained  to  facilitate  mining, 
by  the  Mining  Corpn.  of  Canada,  during  the  spring  and  early  summer  of 
1915.  Previous  to  pumping  out  the  water,  great  quantities  of  sands  and 
slimes  from  concentrating  plants  had  been  discharged  into  the  lake  and 
during  and  after  the  lake's  drainage,  its  basin  was  a  receptacle  for  tailing 
products.  As  the  writer  was  at  work  along  the  shore  line  as  the  lake  was 
being  drained,  he  had  a  good  opportunity  to  observe  the  changes  that 
took  place  as  the  water  was  withdrawn.  Some  adjustments  between 
the  incoming  sands  and  the  mud  in  the  lake  had  taken  place  before 
pumping  was  commenced.  One  of  the  most  interesting  results  was  the 
appearance  of  a  small  dome  in  a  path  the  writer  traversed  twice  a  day  for 
several  months;  he  remembers  distinctly  the  difficulty  of  crossing  this. 

Cobalt  Lake  owed  its  existence  to  the  gouging  out  of  a  rock  basin  by 
glaciation.  The  long  axis  of  the  basin  closely  follows  the  strike  of  a 
thrust  fault  of  about  500  ft.  (160  m.)  vertical  displacement.  The  lake 
was  originally  shaped  somewhat  as  shown.  The  length  was  about  3000 
ft.  (914.4  m.),  the  width  at  the  lower  lobe  was  about  1000  ft.,  and  the 
width  at  the  narrows  probably  400  to  500  ft.  The  original  depth  of 
water  varied  from  20  to  30  ft.  (6.1  to  9.1  m.),  near  where  the  island  later 
was  formed,  to  60  to  70  ft.  (23.6  to  27.6  m.)  in  the  widest  part  of  the  lower 
lobe.  At  the  narrows,  the  depth  was  30  to  40  ft.  Above  the  bed  rock 
was  sand,  with  boulders  near  the  bottom,  and  mud. 

During  the  building  of  the  railroad  in  1903,  considerable  filling  was 
done  along  the  right  of  way.  With  the  commencement  of  mining  opera- 
tions, about  1905,  waste  rock  and  mill  tailings  were  dumped  into  the 
lake.  One  of  the  mining  companies  operated  a  hydraulic  giant  to  remove 
the  glacial  debris  from  several  hundred  acres  of  rock  surface;  much  of 
the  sand  and  clay  from  this  operation  was  deposited  in  the  lake.  About 
1,500,000  tons  of  mill  tailings,  composed  of  sands  and  slimes,  were  dis- 
charged into  the  lake's  waters  previous  to  1915.  Most  of  this  material 


*Published  by  permission  of  R.  O.  Conkling,  chief  geologist,  Roxana  Petroleum 
Corpn. 

t  Geologist  in  charge  Louisiana  Division,  Roxana  Petroleum  Corpn. 


M.    ALBERTSON 


419 


settled  near  the  point  of  discharge  but  the  fine  slimes  spread  throughout 
the  lake  basin  Four  artificial  deltas  were  formed  by  tailings  from 
various  concentrating  mills,  somewhat  as  shown  along  the  upper  end  of 
the  lake. 

The  mud  of  the  lake  bottom  was  a  thin  black  oozy  slime,  much  too 
thin  to  support  a  man's  weight  and  too  thick  to  swim  in.  Its  specific 
gravity  was  much  less  than  that  of  the  sands  and  slimes  coming  in; 
probably  it  was  not  much  greater  than  that  of  water.  The  incoming 


FIG.  1. — PLAN  SHOWING  LOCATION  OF  DOMES,  ISLAND,  TAILING  PILES,  ETC. 

material  pushed  it  aside  in  places  and  caused  it  to  bow  up  as  islands 
and  near  islands  in  other  places.  The  main  part  of  the  slimes  from  the 
tailing  discharge  at  2,  settling  over  the  narrow  part  of  the  lake  bottom, 
strengthened  the  mud  layer.  Much  of  the  mud  from  the  upper  end  of 
the  lake  was  forced  out  toward  the  center  of  the  upper  lobe.  After  the 
pumps  had  lowered  the  water  level  a  few  feet,  an  island  a  few  hundred 
feet  in  diameter  appeared. 

Small  domes  appeared  near  the  shore  at  several  points.  After  the 
upper  end  of  the  lake  was  entirely  drained,  a  large  mud  dome  appeared  in 
about  the  middle  of  the  narrows.  It  is  perfectly  clear  that  the  weight  of 
the  sands  and  slimes  became  too  great  to  be  supported  by  the  thin  oozy 
mud  and  consequent  buckling  resulted  in  the  formation  of  a  dome. 

The  process  of  adjustments  that  brought  the  lake  domes  into  exis- 
tence is  conceived  to  have  gone  on  somewhat  as  follows:  At  the  points 


420      ISOSTATIC   ADJUSTMENTS  IN   THEIR   RELATION  TO   OIL   DOMES 

where  the  tailings  were  discharged  into  the  lake,  the  mud,  which  was 
less  dense  and  in  a  jelly-like  condition,  was  forced  aside.  Since  the 
tailings  entered  the  upper  basin  of  the  lake  from  several  well  distributed 
points  along  its  shores  the  mud  was  forced  toward  the  center  of  the  lake. 
At  the  same  time  a  thin  layer  of  fine  sands  and  slimes  was  deposited  over 
the  whole  of  the  lake  bottom,  but  chiefly  near  the  shore  and  in  a  fan-like 
arrangement  from  the  points  of  tailing  discharge.  The  effect  of  this  was 
to  strengthen  the  mud  layer  near  the  shore  and  to  weigh  it  down  so 
that  the  mud  layer  was  weakest  in  the  center  of  the  lake.  When  the 
weight  of  the  sands  became  sufficient  for  the  sand  to  displace  the  mud  the 
displacement  occurred  where  the  mud  layer  was  weakest. 

It  is  the  writer's  conclusion  that  domal  structures  have  originated  in 
this  manner  in  the  Tertiary  deposits  of  the  Mississippi  embayment  re- 
gion and  that  these  structures  of  the  Tertiary  are,  in  many  cases  at  least, 
non-existent  in  the  more  compacted  Cretaceous  formations  under  them. 
Thus  a  dome  structure  in  surface  formations  does  not  necessarily  mean  a 
dome  in  the  Cretaceous  oil-bearing  sediments. 

If  this  process  is  active  in  one  region  it  must  be  considered  as  a  struc- 
tural factor  in  all  areas  of  sedimentation.  It  is  suggested  as  a  factor  in 
the  formation  of  certain  domes  observed  in  the  Pennsylvanian  area  of 
Missouri. 

During  1911,  1912,  and  1913,  the  writer,  then  a  geologist  for  the 
Missouri  Bureau  of  Geology  and  Mines,  became  well  acquainted  with 
minor  dome  structures  that  characterize  the  Pennsylvanian  strata  of 
northern  Missouri.  Some  of  these  domes  are  shown  on  a  structural 
map  of  Kansas  City.1  Many  others  are  known  in  the  coal  mines  of  the 
state.  The  origin  of  these  domes  has  long  been  a  puzzle.  It  is  of  course 
possible  that  they  are  entirely  the  result  of  regional  folding  stresses,  but 
this  view  does  not  appear  entirely  logical. 

1McCourt,  Albertson  and  Bennett:  Missouri  Bur.  Geol.  and  Mines,  Geology  of 
Jackson  County  (1917)  14  [2]  PL  xvi. 


BIOGRAPHICAL  NOTICE  421 


Anthony  F.  Lucas 

ANTHONY  F.  LUCAS  died  suddenly  at  his  home  in  Washington,  D.  C., 
on  Sept.  2,  1921.  Captain  Lucas,  as  he  was  known  to  us,  was  born  in 
Dalmatia,  Austria,  in  1855,  of  Montenegrin  ancestry.  He  was  graduated 
as  an  engineer  at  the  Polytechnic  of  Gratz  and  served  in  the  Austrian 
Navy  as  second  lieutenant.  In  1879,  he  obtained  leave  of  absence  and 
visited  an  uncle  in  the  United  States.  After  an  extension  of  this  leave  of 
absence,  in  order  to  undertake  an  engineering  engagement  in  the  lumber 
district  of  Michigan,  where  he  resided,  he  decided  to  become  an  American 
citizen.  He  was  naturalized  in  May,  1885. 

His  name  was  Luchich,  but  as  his  uncle  had  adopted  the  name  of 
Lucas,  which  was  more  easily  pronounced  by  Americans,  from  his 
entrance  to  this  country,  he  used  this  Anglo-Saxon  form.  Without 
knowing  this  fact,  upon  first  meeting  him  a  person  was  sometimes  sur- 
prised to  note  the  rather  Germanic  pronunciation  of  the  Captain. 

Although  he  subsequently  revisited  Austria  with  Mrs.  Lucas,  he  made 
his  permanent  home  at  Washington,  D.  C.  His  son  served  with  distinc- 
tion in  the  A.  E.  F.  during  the  World  War. 

His  activities  in  this  country  as  a  mining  engineer  were  at  first  in 
Colorado  and  later  in  salt  mining  at  Petit  Anse  and  Belle  Isle,  La.  During 
his  salt  investigations,  his  attention  was  directed  toward  the  possibility 
of  oil  in  the  Gulf  Coast  region  and  in  January,  1901,  his  well,  the  "Lucas 
Gusher,"  on  Spindle  Top,  Tex.,  started  a  new  era  in  the  oil  business  and 
his  reputation  as  discoverer  made  him  famous  throughout  the  world. 

Captain  Lucas  became  a  member  of  the  A.  I.  M.  E.  in  1895.  During 
1914,  1915,  1918,  and  1919,  he  was  chairman  of  the  Petroleum  and  Gas 
Committee  of  the  Institute  and  was  at  all  times  prominent  in  Institute 
affairs. 

As  to  the  personality  of  Captain  Lucas,  the  lasting  impression  is  of  a 
courteous  hospitable  gentleman,  genial,  affable,  obliging,  and  helpful  with 
his  advice  or  assistance  to  any  colleague.  He  was  sincere,  honest,  firm 
against  all  obstacles,  backing  his  judgment  with  his  own  hard  work  along 
any  course  which  he  had  determined  to  be  correct. 

His  value  in  the  engineering  world  lies  mainly  in  the  petroleum  indus- 
try. In  the  oil  business  all  wild-catters  are  pioneers  that  deserve  credit 
and  gratitude  upon  their  success.  There  are,  however,  names  that  par- 
ticularly stand  out  in  our  history.  Drake  conquered  such  obstacles  as 
ridicule,  lack  of  finances,  and  started  the  oil  business.  In  1901,  Captain 
Lucas  had  the  conviction  that  Spindle  Top,  a  dome  rising  about  12  ft. 
above  the  coastal  prairie  south  of  Beaumont,  Tex.,  contained  commercial 
oil.  He  was  scoffed  at  by  practical  oil  men  of  the  East.  Noted  geologists 


422  BIOGRAPHICAL  NOTICE 

were  condemnatory  on  the  ground  that  such  an  occurrence  was  unprece- 
dented. It  was  a  rank  wildcat.  Savage,  Sharp,  and  others  had  tried  to 
drill  wells,  one  at  least,  with  cable  tools,  and  had  given  up,  but  Captain 
Lucas  put  down  one  well,  which  was  ruined  at  about  600  ft.,  having  had  a 
showing  of  heavy  oil.  Obtaining  financial  support,  with  the  J.  M.  Guffey 
Petroleum  Co.,  he  drilled  another  well  to  the  depth  of  less  than  1100  ft. 
In  January,  1901,  this  well  came  in  at  a  rate  estimated  as  high  as  125,000 
bbl.  per  day  and  flowed  wild  for  ten  days  before  it  was  finally  controlled. 


ANTHONY  F.  LUCAS. 

The  discoverer  estimated  the  flow  at  75,000  to  100,000  bbl.,  but  the  above 
figure  is  an  estimate  of  a  civil  engineer  who  gaged  it  by  a  full  6-in.  stream 
of  oil  200  ft.  high  and  what  tests  could  be  made  of  runoff  of  the  oil.  This 
discovery  astounded  the  oil  men  of  the  world. 

It  should  be  recalled  that  for  the  drilling  of  this  well  a  rotary  rig  was 
used;  this  method  was  then  in  its  infancy  (having  been  used  only  in  Cor- 
sicana  and  in  some  water-well  drilling)  so  that  the  wild-catter  had  but 
slight  benefit  of  experience  of  others.  He  was  obliged  to  devise  his  own 


ANTHONY   F.    LOUCAS  423 

methods  of  combating  drilling  difficulties,  and  in  doing  so  earned  rights 
to  patent,  of  which  I  do  not  believe  he  availed  himself. 

I  quote  here  a  question  and  answer  published  in  the  Mining  and 
Scientific  Press  (Dec.  22,  1917) : 

T.  A.  RICKARD. — I  hope,  Captain,  that  you  received  a  proper  financial  reward 
this  time? 

A.  F.  LUCAS. — I  did,  but  my  chief  reward  was  to  have  created  a  precedent  in 
geology  whereby  the  Gulf  Coast  of  the  Coastal  Plain  has  been  and  is  now  a  beehive 
of  production  and  industry. 

We  would  all  have  asked  the  question  and  must  regret  that,  while  his 
later  career  was  undoubtedly  financially  successful,  at  Damon  Mound 
and  some  other  localities  where  our  deceased  fellow  member  wild-catted, 
he  was  too  far  ahead  of  his  time  to  make  further  successes.  The  answer 
was  characteristically  sincere  and  intrinsically  true.  Old  timers  remem- 
ber Beaumont,  a  small  lumber  town  with  mud  streets,  becoming  a  regular 
beehive  during  1901.  We  recall  the  forest  of  derricks  with  overlapping 
legs  on  the  300-acre  Spindle  Top;  the  lakes  of  oil  lying  unused  on  "the 
Hill"  without  proper  transportation  for  removal;  the  hurly  burly  where 
land  was  sold  and  paid  for  at  the  rate  of  one  million  dollars  per  acre;  the 
wild  stock-selling  schemes  that  filled  the  daily  press.  These  are  disagree- 
able though  interesting  sides  of  the  feverish  and  foolish  oil  stampede.  On 
the  opposite  and  wonderful  side,  as  a  direct  result  of  Captain  Lucas' 
perseverance,  was  the  rise  of  legitimate  operators  to  success;  namely,  the 
J.  M.  Guffey  Petroleum  Co.  (The  Gulf  Refining  Co.)  and  The  Texas  Co. 
Further  development  was  stimulated  at  Sour  Lake,  Batson,  Saratoga, 
Humble;  later,  at  Damon  Mound,  Goose  Creek,  Hull  and  other  fields. 

This  all  refers  to  the  Gulf  Coast,  but  why  should  Captain  Lucas  have 
confined  his  influence  to  that  region?  There  are  today,  in  the  Mid-Conti- 
nent and  other  districts,  veritable  powers  in  oil  production  who  had  their 
lessons  on  the  derrick  floors  of  Spindle  Top  rigs  subsequent  to  the  "Lucas 
Gusher." 

Along  the  scientific  side,  there  has  been  much  discussion  of  Coastal 
Plain  problems.  By  such  free  exchange  of  knowledge,  advance  has  been 
made  toward  the  truth,  not  only  as  applicable  to  Texas  and  Louisiana 
but  to  Oklahoma,  California,  and  the  East;  to  Mexico,  South  America, 
and  other  foreign  fields. 

This  is  what  Captain  Lucas  was  after  in  starting  his  oil  venture;  this 
is  what  we  are  after-^the  truth.  We  owe  his  memory  gratitude  for 
starting  a  new  era  in  oil  production  twenty  years  ago,  which  has  had 
tremendous  effect  in  the  professional  and  business  lives  of  all  of  us  down 
to  the  present  time. 

Although  he  considered  himself  "properly  rewarded,"  we  may  believe 
that  even  though  he  was  beyond  want,  he  was  entitled  to  much  greater 
financial  reward  than  he  received.  Certainly  he  deserves  a  prominent 
and  permanent  place  in  oil  history  because  of  his  Spindle  Top  discovery. 

H.  B.  GOODKICH. 


424         ROCK  CLASSIFICATION  FROM  THE  OIL-DRILLER'S  STANDPOINT 


Rock  Classification  from  the  Oil-driller's  Standpoint 

BY  ARTHUR  KNAPP,  M.  E.,  SHREVEPORT,  LA. 
(New  York  Meeting,  February,  1920) 

THE  ordinary  well  log  is  subjected  to  a  great  deal  of  criticism,  much 
of  which  is  well  founded.  Sometimes,  though,  the  difficulty  in  interpret- 
ing the  log  is  due  to  the  fact  that  the  geologist  or  engineer  using  the  logs 
does  not  know  the  limitations  of  the  drilling  method  used.  The  rotary 
drill,  especially,  has  inherent  limitations  that  make  it  difficult  to  secure 
definite  information  at  all  times.  The  identification  of  well-defined  key 
beds  is  about  all  that  can  be  expected  from  the  rotary  log.  The  forma- 
tion in  a  drilled  hole,  as  reported  by  the  driller,  has  a  direct  relation  to  the 
speed  with  which  the  drill  makes  the  hole  or  to  the  reaction  of  the  various 
strata  on  the  bit,  called  the  "feel  of  the  bit. "  When  this  is  not  thoroughly 
understood  by  the  geologist  or  engineer  endeavoring  to  interpret  the  log, 
the  result  is  an  erroneous  correlation  with  other  wells  or  a  discarding  of 
the  log  as  worthless. 

GENERAL  TERMS 

Hard  and  Soft. — Hard  and  soft  are  relative  terms.  In  the  case  of  well 
logs,  they  are  very  misleading  as  they  are  used  in  connection  with  both 
resistance  to  abrasion  and  resistance  to  percussion.  In  technical  rock 
classification,  hardness  is  relative  resistance  to  abrasion.  The  term 
brittleness  is  used  in  connection  with  resistance  to  blows.  These  terms 
are  misleading  to  the  geologist  or  engineer  who  is  not  familiar  with  both 
the  cable-tool,  or  standard  tool,  method  of  drilling  and  the  rotary  method. 
In  the  case  of  the  standard  tools,  the  driller's  report  of  the  hardness  of  the 
formation  is  in  terms  of  its  resistance  to  blows.  For  instance,  a  cable- 
tool  driller  might  be  able  to  make  from  30  to  50  ft.  a  tour  in  a  brittle 
limestone,  which  he  would  call  soft  and  at  the  same  time  he  might  call  a 
relatively  soft  (from  a  purely  mineralogical  standpoint)  gypsum  hard, 
because  it  is  somewhat  elastic  and  is  not  readily  broken  by  blows.  The 
rotary  driller  would  reverse  the  terms.  The  limestone  is  hard  in  that  it 
resists  the  abrasive  action  of  the  bit,  while  the  gypsum  might  be  soft  in 
that  it  is  readily  cut  by  the  rotary  bit.  It  is  rare  that  wells  drilled  by  the 
standard  tools  are  correlated  with  those  drilled  by  the  rotary,  but  the 
technologist  who  has  worked  with  well  logs  from  one  system  might  be 
misled  when  working  with  the  other. 


ARTHUR  KNAPP  425 

Sticky. — With  the  rotary  drill,  a  formation  is  sticky  which  cuts  in 
large  pieces  that  adhere  to  the  bit  and  drill  pipe.  A  formation  that  is 
sticky  with  the  rotary  is  usually  sticky  with  the  cable  tools.  On  the 
other  hand,  formations  are  encountered  in  which  the  cable  tools  stick, 
either  owing  to  the  elasticity  of  the  formation  or  to  the  fact  that  the 
drilled-up  particles  do  not  mix  readily  with  the  water  in  the  hole  and  settle 
so  quickly  as  to  stick  the  bit.  These  formations  might  not  appear 
sticky  to  the  rotary  driller. 

Sandy. — This  term  may  be  used  quite  accurately  by  the  cable-tool 
driller.  He  obtains  samples  of  the  formation  through  which  he  passes,  of 
sufficient  size  to  determine  the  relative  amount  of  sand  to  clay  or  sand 
to  shale  in  any  formation.  In  the  case  of  the  rotary  drill,  this  term  is 
misleading. 

The  rotary  well  is  drilled  with  the  aid  of  a  "mud"  of  varying  density 
It  is  usually  thought  of  as  a  mixture  of  clay  and  water  with  a  small  amount 
of  suspended  sand.  As  a  matter  of  fact  this  mud  often  contains  as  high 
as  40  to  50  per  cent.  sand.  This  sand  tends  to  destroy  the  col- 
loidal properties  of  the  mud  and  the  action  of  the  mud  on  the  walls  of 
the  well  is  the  same  as  a  thin  mud  with  less  fine  sand.  The  water  would 
tend  to  exchange  the  suspended  sand  for  mud  from  the  walls  of  the  well, 
thus  thinning  the  well  wall.  It  is  impossible  to  settle  out  the  very  fine 
sand  in  any  rotary  mud.  An  easy  and  quick  way  to  separate  the  two  for 
examination  is  to  fill  the  glass  of  a  centrifugal  separator  half  full  of  mud 
and  add  a  saturated  solution  of  common  salt.  The  sand  will  be  thrown 
to  the  bottom  when  the  machine  is  turned  for  a  short  time.  The  mud 
alone  can  be  turned  indefinitely  without  any  appreciable  separation. 

Any  change  in  the  density  of  the  mud  changes  its  capacity  to  carry 
sand.  Even  a  small  shower  falling  on  the  slush  pit  will  change  the 
density  enough  to  cause  some  of  the  suspended  sand  to  be  precipitated. 
These  properties  of  the  mud  lead  to  error  in  the  observation  of  the  forma- 
tion. If  a  clay  formation  containing  a  moderate  amount  of  sand  is 
encountered  while  drilling  in  a  mud  low  in  sand  content,  the  mud  will 
absorb  most  of  the  sand,  which  will  not  settle  out  in  the  overflow  ditch 
and  its  presence  in  the  formation  will  not  be  noted,  if  not  felt  by  the  action 
of  the  bit  in  drilling.  If,  some  time  later,  the  mud  is  thinned  by  adding 
water  this  sand  will  appear  in  the  overflow  and  may  be  attributed  to  a 
formation  many  feet  below  the  one  from  which  it  actually  originated. 

The  so-called  "  jigging "  action  of  the  rising  column  of  mud  on  the 
sand  or  cuttings  also  leads  to  misinterpretation.  I  have  often  heard 
drillers  remark  that  the  deeper  you  drill,  the  finer  the  sand.  This  is  not 
true,  but  it  is  true  that  the  deeper  you  drill,  the  finer  the  sand  or 
cuttings  brought  to  the  surface  by  the  mud.  The  coarser  particles  have 
been  pounded  into  the  walls  of  the  well  or  broken  and  the  deeper  the  well, 
the  more  opportunity  the  drill  pipe  has  had  to  do  this. 


426         KOCK    CLASSIFICATION   FROM   THE   OIL-DRILLER'S   STANDPOINT 

A  change  in  the  speed  of  pumping  the  mud  also  causes  a  change  in  the 
amount  and  size  of  the  cuttings  that  appear  at  the  surface.  Thus,  in  the 
case  of  the  rotary,  "sandy  "  may  have  little  or  no  meaning  when  applied  to  a 
formation.  The  term  sandy  is  often  used  in  contradistinction  to  sticky. 
A  formation  that  drills  easily  and  is  not  sticky  is  often  put  down  as  sandy 
because  sand  tends  to  interfere  with  the  stickiness.  Sand  does  not  always 
account  for  the  lack  of  stickiness  but  the  latter  is  often  attributed  to  its 
presence. 

Dark  and  Light. — This  brings  up  the  subject  of  color.  The  first 
question  is  the  age  of  the  specimen  when  the  color  is  determined.  A  wet 
specimen,  fresh  from  the  hole,  has  an  entirely  different  color  from  the 
same  specimen  dried.  Specimens,  when  dried,  bleach  and  deteriorate. 
Many  of  them  air  slack  or  oxidize  and  change  composition  altogether. 
The  terms  light  and  dark  should  be  used  only  for  the  extremes.  They 
are,  in  general,  relative  and  therefore  very  indefinite  and  misleading. 
A  sample  of  wet  shale  examined  under  an  electric  light  might  appear 
many  shades  darker  than  in  day  light.  It  is  better  to  use  a  definite  name 
than  the  words  light  and  dark ;  such  as  slate-colored  or  chocolate-colored 
shale.  On  the  other  hand,  color  is  not  very  important  except  in  key  beds, 
which  are  usually  of  extreme  shades,  either  very  light  or  very  dark. 

FORMATIONS 

Clay,  Gumbo,  Tough  Gumbo. — Clay  is  readily  recognized  by  the  "feel 
of  the  bit"  while  drilling  with  either  cable  tools  or  rotary.  To  some  drill- 
ers all  clay  is  gumbo  while  to  others  gumbo  is  only  sticky  clay.  Some 
clays  have  the  property  of  cutting  in  large  pieces  but  do  not  adhere 
excessively  to  the  bit  and  drill  pipe  and  are  designated  as  "tough." 

Sand,  Packed  Sand,  Water  Sand,  Quicksand,  Heaving  Sand,  Oil  Sand, 
Gas  Sand. — Free,  uncemented  sand  is  easily  recognized  by  the  feel  of  the 
tools  in  both  systems  of  drilling.  In  rotary  territory,  we  often  run  across 
the  term  "packed  sand."  This  is  a  sand  that  is  slightly  cemented  with 
some  soft  easily  broken  cementing  material,  such  as  calcium  carbonate. 
It  cuts,  when  drilled  with  a  rotary,  with  much  the  same  feeling  as  when 
cutting  crayon  with  a  knife.  The  cementing  material  is  dissolved  by  the 
mud  or  the  sand  grains  are  all  broken  apart  before  reaching  the  surface, 
so  that  the  driller  finds  only  sand  in  the  overflow.  A  microscopic  exami- 
nation of  sands  from  the  overflow  often  shows  cementing  material  to  be 
present  when  not  suspected  by  the  action  of  the  bit. 

Water  sand  is  a  sand  containing  water.  There  is  no  specific  sand 
associated  with  water;  any  porous  formation  may  or  may  not  contain 
water.  In  the  case  of  both  rotary  and  cable  tools,  sand  that  is  fresh  and 
bright  and  has  a  clean  appearance  when  taken  from  the  well  impresses  one 
as  being  a  water  sand  and  probably  does  come  from  a  wet  stratum.  If 


AKTHTJR   KNAPP  427 

it  so  happens  that  the  sand  has  been  thoroughly  mixed  with  the  mud  in 
the  hole  so  that  each  particle  is  colored  by  a  film  of  mud,  it  does  not  appear 
fresh  and  clean  and  does  not  give  the  impression  of  being  a  water  sand. 
This  may  be  because  the  formation  from  which  it  came  was  dry  or  nearly 
so  or  simply  because  conditions  were  right  for  the  quick  coloring  of  the 
sand  by  the  mud.  Whether  a  given  porous  formation  is  a  water  stratum 
or  not  can  only  be  determined  by  testing.  It  is  only  in  rare  cases  that 
the  hydrostatic  pressure  is  sufficient  to  cause  the  thinning  of  the  mud  in  a 
rotary  hole.  While  drilling  in  a  dry  hole  with  the  cable  tool,  it  is  known 
at  once  how  prolific  a  porous  stratum  is. 

A  sand  containing  no  cementing  material  nor  clay  very  often  caves 
badly  in  the  hole.  If  this  sand  settles  with  such  rapidity  as  to  threaten 
to  stick  the  tools,  it  is  designated  quicksand.  Such  a  free  sand  may,  on 
the  other  hand,  have  such  properties  that  it  seems  to  tend  to  float.  It 
not  only  caves  but  fills  the  hole  above  its  original  horizon,  sometimes 
heaving  clear  to  the  surface.  This  sand  is  called  a  heaving  sand.  The 
presence  of  gas  or  a  high  hydrostatic  head  often  accounts  for  the  heaving 
of  the  sand. 

An  oil  sand  is  a  sand  containing  oil.  There  is  no  particular  sand  which 
is  associated  with  oil;  any  porous  stratum  might  contain  oil.  A  porous 
stratum  containing  oil  is  often  called  a  sand  although  it  may  actually 
be  a  limestone. 

A  gas  sand  is  any. sand  containing  gas;  even  a  hard  limestone  is  some- 
tunes  designated  as  a  gas  sand. 

Boulders  and  Gravel. — True  boulder  formations  are  rarely  encountered 
in  drilling  for  oil.  They  are  encountered  above  the  Trenton  in  Ohio  and 
Indiana  and  occasionally  in  California.  Concretions  are  often  encoun- 
tered which  fall  into  the  hole  and  follow  the  bit  for  some  time  and  are  re- 
ported as  boulders.  A  green  rotary  driller  will  report  boulders  when  he 
is  drilling  in  sticky  gumbo,  which  causes  the  bit  to  jump  excessively. 

Gravel  is  also  quite  rare  and  as  it  is  a  question  what  is  coarse  sand  and 
what  is  gravel,  a  report  of  gravel  may  mean  coarse  sand.  The  cable 
tools  will  bring  up  gravel  so  that  it  may  be  recognized.  Loose  shale  or 
oyster  shells  may  be  reported  as  gravel  by  the  rotary  driller. 

Shale. — Shale,  to  many  drillers,  is  only  that  kind  of  true  shale  which 
appears  in  the  overflow,  or  bailer,  in  flakes,  that  is,  laminated  shale  with 
well-defined  bedding.  Other  drillers  include  formations  that  are  sedimen- 
tary in  character  and  are  consolidated  enough  to  appear  in  the  overflow, 
or  bailer,  in  pieces  as  large  as  a  pea  or  larger.  They  usually  call  a  shale 
too  hard  to  scratch  with  the  finger  nail  rock,  particularly  in  rotary  terri- 
tory. The  rotary  driller  finds  it  hard  to  differentiate  between  hard  shale 
and  soft  limestone. 


428       ROCK   CLASSIFICATION   FROM   THE    OIL-DRILLER'S   STANDPOINT 


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ARTHUR   KNAPP  429 

Rock,  Gas  Rock,  Chalk  Rock,  Sand  Rock,  Sandstone,  Shell,  Shell  Rock, 
Flinty  Rock,  Limestone,  Lignite.- — When  the  rotary  driller  strikes  any- 
thing hard  and  does  not  know  what  it  is,  he  puts  down  rock.  If  this 
hard  substance  is  a  concretion  near  the  surface,  it  is  a  rock  just  the  same 
as  the  most  consolidated  formations  deeper  down.  The  cable-tool  driller 
has  a  much  better  general  knowledge  and  a  much  better  chance  to  get 
samples  and  hunts  for  some  name  to  apply  to  the  formation. 

A  gas  rock  is  any  rock  formation  containing  gas;  the  term  is  applied 
to  both  sandstone  and  limestone, 

Chalk  rock  is  usually  readily  recognized  by  both  rotary  and  cable- 
tool  drillers.  It  is  usually  white  or  very  light  in  color  and  quickly 
changes  the  rotary  mud  from  its  usual  dark  gray  to  almost  white. 

Sand  rock,  or  sandstone,  is  usually  recognized  by  the  rotary  driller, 
except  when  it  is  so  soft  as  to  be  classified  as  packed  sand.  The  harder 
formations  appear  in  the  overflow  in  pieces  sufficiently  large  to  be  readily 
recognized.  The  cable-tool  driller  is  able  to  recognize  sandstone  and  all 
other  hard  formations  as  he  finds  large  fragments  in  the  bailer. 

Shell  is  a  very  misleading  term.  If  a  driller,  either  rotary  or  cable- 
tool,  drills  from  a  soft  formation  into  a  hard  one  he  gives  it  what  he  con- 
siders its  proper  name.  If,  however,  after  drilling  for  a  short  distance, 
he  goes  back  into  a  soft  formation  again  he  is  liable  to  put  down  shell. 
This  shell  may  be  from  a  few  inches  to  a  foot  or  two  in  thickness,  it  means 
a  thin  layer  or  shell  of  rock. 

Shell  rock  means  a  rock  formation  containing  fossil  shells,  unless  the 
driller  is  very  careless  or  misunderstands  the  term  shell,  in  which  case 
he  may  put  down  shell  rock,  meaning  a  thin  shell  of  rock. 

Most  cable-tool  drillers  are  able  to  distinguish  the  characteristic 
fracture  of  flint  and  their  report  of  flint  or  flinty  rock  may  usually  be  re- 
lied on.  Flint  is  very  seldom  encountered  with  the  rotary  and  when 
reported  in  a  structure  in  which  it  is  not  likely  to  be  found  is  probably 
used  to  designate  a  very  brittle  limestone,  flinty  in  character. 

The  cable-tool  driller's  report  of  limestone  is  usually  correct  but  the 
rotary  driller  does  not  always  distinguish  between  hard  shale  and  limestone. 

Lignite  is  used  to  designate  both  the  petrified  and  the  bituminous 
forms  of  wood  found  in  drilling.  Even  when  the  wood  has  not  lost  its 
fibrous  character,  it  is  often  designated  as  lignite. 

Shells. — In  rare  instances,  solid  beds  of  shells  are  encountered.  They 
are  easily  recognized  as  such  with  the  cable  tools  but  with  the  rotary  they 
may  not  be  recognized  and  may  be  reported  as  sand  or  gravel,  depending 
on  the  feel  of  the  bit  while  drilling.  When  mixed  with  clay  or  sand, 
shells  usually  appear  in  the  log  as,  "sand  with  shells "  or  "  clay  with  shells." 


430  INVESTIGATIONS    CONCERNING    OIL-WATER  EMULSION 


Investigations  Concerning  Oil-water  Emulsion* 

BY  ALEX.  W.  Me  COY,  BARTLESVILLE,  OKLA.,  H.  R.  SHIDEL,  EL  DORADO,  KANS., 
AND  E.  A   TRACER,  BARTLESVILLE,  OKLA. 

(Chicago  Meeting,  September,  1919) 

SAMPLING  of  the  fluid  from  oil  wells  for  percentages  of  oil,  emulsified 
oil,  and  water  during  the  last  two  years  has  brought  out  some  interesting 
facts  concerning  oil-water  emulsion.  This  result  led  to  a  laboratory 
investigation  of  emulsion,  which  substantiated  the  conclusions  made  from 
the  field  observations.  The  purpose  of  this  paper  is  to  present  the  infor- 
mation collected,  the  laboratory  experiments,  and  our  interpretation  of 
the  same.  In  order  to  define  emulsified  oil  exactly,  give  its  synthesis  and 
origin,  and  to  show  how  and  when  it  is  formed  in  the  wells,  the  work  was 
necessarily  divided  into  two  separate  lines — laboratory  work  and  field 
observations.  It  is  hoped  that  this  study  may  lead  to  a  discussion  of  such 
points  so  that  the  petroleum  engineer,  geologist,  or  technologist  may  be 
benefited  by  its  practical  bearing  on  oil-field  management.  Special 
credit  is  due  Mr.  Everett  Carpenter,  chief  geologist  of  the  Empire  Gas 
&  Fuel  Co.,  for  his  assistance  and  cooperation  in  this  work. 


LABORATORY  INVESTIGATIONS  ON  EMULSIFIED  OIL 

Laboratory  investigations  were  conducted  in  an  attempt  to  learn  the 
composition  and  some  of  the  properties  of  emulsified  oil,  or  B.  S.,  as  it  is 
more  commonly  called,  also  to  demonstrate,  by  laboratory  methods, 
how  B.  S.  may  be  formed  under  conditions  similar  to  those  existing 
at  the  time  a  well  is  being  pumped,  and  how  it  may  be  broken  down. 
Literature  bearing  on  this  subject  is  widely  scattered  and  very  limited  in 
scope.  Bacon  and  Hamor  define  B.  S.,  or  bottom  settlings,  as  "earthy 
matter,  inert  organic  matter,  or,  in  the  case  of  Pennsylvanian  petro- 
leum, an  emulsion  of  paraffin  wax  and  water,  which  accompanies  crude 
oil."  In  this  discussion  we  will  limit  the  term  B.  S.  to  that  heavy, 
dark-brown  emulsion,  composed  of  a  physical  mixture  of  water,  oil, 
and  air  with  some  included  inert  matter,  either  organic  or  inorganic. 

Possibly  the  first  step  in  a  description  of  this  product  should  be  a 
description  of  its  physical  properties,  but  since  most  operators  are  quite 

*  Published  through  the  courtesy  of  the  Empire  Gas  &  Fuel  Co  Read  before  the 
Tulsa  Section,  February,  1919. 


ALEX.   W.    MCCOY,    H.    R.    SHIDEL   AND   E.    A.    TRACER  431 

familiar  with  emulsified  oil,  and  because  the  physical  discussion  will  be 
better  understood  after  one  is  familiar  with  the  microscopic  studies,  that 
side  of  the  investigation  will  be  presented  first. 

A  thin  layer  of  emulsified  oil  under  the  microscope  appears  as  a  yellow- 
ish to  brownish  green,  solid  mass  of  small  bubbles,  with  an  occasional 
larger  colorless  bubble  of  water  and  smaller  brownish  globules  of  oil. 
Fig.  1  shows  this  relation.  All  of  the  large  and  most  of  the  small, 
colorless  bubbles  are  composed  of  water  surrounded  by  an  oil  film.  The 
dark  spots  are  bubbles  of  oil.  The  dark  material  surrounding  and  be- 
tween the  bubbles  is  oil.  The  few,  very  bright  small  bubbles  are  air. 

Careful  examination  shows  that  permanently  emulsified  oil  is  com- 
posed of  millions  of  small  bubbles  of  water  that  range  in  diameter  from 
0.004  to  0.020  mm.,  the  most  numerous  having  a  diameter  of  about 
0.016  mm.  These  bubbles  are  packed  very  closely  together  in  a  medium 
of  oil,  the  average  distance  between  them  being  less  than  one-half  their 
diameter.  Scattered  in  and  among  these  very  small  bubbles  is  a  rela- 
tively small  number  of  larger  bubbles  of  water,  which  vary  in  diameter 
from  0.034  to  0.070  mm.  There  is  also  about  one-tenth  this  number  of 
still  larger  bubbles  of  water,  which  vary  in  diameter  from  0.110  to  0  250 
mm.  It  is  about  these  larger  sizes  that  the  very  smallest  bubbles  are 
concentrated.  There  are  a  few  bubbles  of  either  water  or  air,  with  a 
diameter  of  0.004  mm.,  scattered  among  the  "groundmass"  of  small 
bubbles,  which  are  about  0.016  mm.  in  diameter;  but  there  are  many 
very  small  ones  located  in  the  oil  film  that  envelops  the  large  water 
bubbles.  This  arrangement  can  be  clearly  seen  by  noticing  the  large 
bubbles  of  water  in  Fig.  1.  Nearly  all  of  the  small  bubbles  are  filled  with 
water;  a  few  contain  air.  If  the  material  is  heated  very  slightly,  the 
small  bubbles  begin  a  more  or  less  constant  motion  toward  and  away  from 
the  larger  bubbles.  The  motion  is  eddying  in  nature  and  becomes  more 
rapid  as  the  heat  is  increased.  Occasionally  one  of  the  small  bubbles 
drifts  away  from  the  current  that  causes  it  to  move  about  the  larger 
bubble  and  moves  along  the  oil  passage  between  the  water  bubbles  of  the 
"groundmass,"  finally  attaching  itself  to  some  large  bubble. 

There  are  also  small  globules,  or  isolated  patches  of  oil,  0.003  to 
0.050  mm.  in  diameter,  trapped  among  the  water  bubbles.  Some  of  these 
are  perfectly  spherical  in  outline  while  others  have  no  definite  shape. 
These  globules  of  oil  are  usually  composed  of  oil  free  from  foreign  matter 
and  appear  dark  reddish  brown  in  color.  Some  of  these  may  also  be  seen 
in  Fig.  1. 

Air  bubbles  of  any  considerable  size,  that  is,  over  0.020  mm.  in  diame- 
ter, are  rarely  found  in  emulsified  oil  that  has  stood  for  any  length  of 
time.  This  is  probably  due  to  the  fact  that  the  films  surrounding  the  air, 
after  they  reach  this  size,  are  easily  broken  either  by  mechanical  agita- 
tion of  the  mass  or  by  expansion  of  the  air  due  to  heating.  The  air 


432 


INVESTIGATIONS    CONCERNING    OIL-WATER   EMULSION 


bubbles  are  surrounded  by  a  layer  or  film  of  oil,  a  film  of  water,  and  a 
second  film  of  oil.  Fig.  2  shows  the  oil  film  on  the  outside  of  an  air  bubble. 
There  appears  to  be  a  constant  shifting  or  stretching  of  these  films,  which 
is  most  easily  seen-  by  watching  the  water  film.  The  oil  films  appear  to 


FIG.  1. — PHOTOMICROGRAPH  OP  TYPICAL  B.  s.     x  450. 

slide  about  or  change  their  tension,  causing  streaks  to  develop  in  the 
water  film,  which  appear  similar  to  convection  currents  or  the  streams  of 
water  that  move  about  on  the  surface  of  a  soap  bubble.  Possibly  this 


FlG.    2. — OlL   FILM   AROUND    AN    AIR 
BUBBLE.       X    450. 


FIG.  3. — WATER  FILM  BETWEEN  THE  OIL 
FILMS  OF  AN  AIR  BUBBLE.     X  450. 


movement  is  caused  by  the  heating  due  to  the  light  from  the  condenser 
or  the  microscope,  for  a  large  bubble  of  air  seldom  lasts  over  5  min.,  in 
the  field  of  view,  without  breaking;  or  it  may  be  due  to  evaporation  of  the 
lighter  constituents  in  the  outer  oil  film,  since  such  bubbles  can  only  be 


ALEX.    W.    MCCOY,    H.    E.    SHIDEL   AND    E.    A.    TRACER  433 

studied  by  isolating  them  in  a  thin  layer  with  the  upper  part  of  the  bubble 
exposed  to  the  air.  The  large  bubble  shown  in  Fig.  3  was  taken  with  the 
water  film  in  focus  and  will  give  some  idea  of  the  irregularities  in  this 
film.  The  circular  shadows  visible  are  from  small  bubbles  on  the 
opposite  side  of  this  bubble.  ^ 

The  purity  of  the  oil  that  fills  the  spaces  between  the  water  bubbles 
varies  widely  with  different  samples.  In  some  cases  the  oil  is  practically 
free  from  foreign  matter,  while  in  others  it  is  very  muddy  in  appearance. 
The  water  bubbles,  in  a  sample  composed  of  dirty  oil,  do  not  have  as 
definite  sizes  as  they  do  in  samples  that  are  comparatively  free  from  dirt. 


FlG.    4. B.    S.    CONTAINING    HIGH    PERCENTAGE    OF   FOREIGN  MATTER.        X    450. 

Fig.  4  shows  a  sample  containing  much  foreign  matter.  In  general,  it 
was  found  that  the  samples  that  tend  to  be  most  permanent  are  those 
in  which  the  oil  contains  a  large  percentage  of  suspended  matter;  and 
those  samples  that  are  easily  broken  down  contain  relatively  clean  oil. 

DEFINITION  OF  -EMULSIFIED  OIL 

The  appearance  of  emulsified  oil,  under  the  microscope,  is  so  different 
from  that  of  good  crude  oil  that  the  two  would  never  be  confused  by 
such  an  examination.  Of  course,  there  are  gradations  from  crude  oil 
to  emulsified  oil.  A  sample  of  good  oil,  under  the  microscope,  appears 
much  the  same  as  it  does  in  a  cylinder,  with  the  exception  that  the  foreign 
matter  in  suspension  is  visible  and  an  occasional  water  bubble  will  be 
seen.  As  the  oil  approaches  emulsification,  the  water  bubbles  become 

VOL.  LXV. 28. 


434  INVESTIGATIONS    CONCERNING   OIL-WATER   EMULSION 

closer  and  closer  together,  until  finally  they  appear  to  be  touching  each 
other,  when  examined  with  a  low-power  lens.  Just  when  an  oil  ceases 
to  be  crude  oil  and  is  to  be  classified  as  emulsified  depends  more  on  its 
physical  appearance  and  plastic  properties  than  on  characteristics  re- 
vealed by  microscopic  examination.  It  might  be  said  that  oil  in  which 
the  water  bubbles  are  spaced  closer  together  than  their  diameter  should 
be  termed  emulsified.  This  definition  would  fit  most  cases,  but  there 
would  be  exceptions  because  of  the  importance  of  suspended  matter  in 
forming  emulsified  oil.  An  emulsion,  containing  water  bubbles  with  this 
spacing,  that  has  a  low  specific  gravity  and  is  free  from  suspended  matter 
might  be  sufficiently  mobile  to  be  turned  into  a  pipeline  run  and  the 
entire  run  treated  by  a  simple  heating  process.  An  emulsion  having  the 


FlG.  5. B.  S.  FREE  FROM  FOREIGN       FlG.  6. B.  S.  WITH  HIGH  PERCENTAGE 

MATTER.  OF  FOREIGN  MATTER. 

same  spacing  of  the  water  bubbles  but  composed  of  a  heavier  oil  and 
containing  a  considerable  amount  of  suspended  matter  would  be  quite 
viscous  and  could  be  treated  only  by  the  use  of  a  complex  steaming 
plant.  Or,  the  water  bubbles  might  be  twice  as  far  apart  and  yet  the 
emulsified  oil  would  be  more  viscous  than  the  first  sample,  because  of 
the  difference  in  the  character  of  the  oil  and  the  amount  of  foreign 
matter  in  suspension.  These  varying  factors  make  it  difficult  to  establish 
a  dividing  line  between  crude  oil  and  emulsified  oil,  based  on  microscopic 
examination,  although  usually  such  an  examination  will  reveal  instantly 
the  degree  of  emulsification,  by  revealing  the  spacing  of  the  water  bubbles 
and  the  amount  of  suspended  matter  present. 

Figs.  5  to  9  will  give  some  idea  of  the  appearance  of  different  types 
of  emulsified  oil  under  the  microscope.  Fig.  5, shows  a  sample  of  per- 
manent B.  S.  that  is  practically  free  from  foreign  matter.  Fig.  6  shows 
very  heavy  and  dirty  B.  S.  Fig.  7  shows  B.  S.  that  contains  very  little 
suspended  matter.  In  Fig.  8,  the  sample  is  only  partly  emulsified;  the 
group  of  small  bubbles  in  the  lower  left-hand  side  marks  the  place  where 
a  large  air  bubble  broke  just  as  the  picture  was  being  taken.  Fig.  9 
shows  B.  S.  that  is  drying  up  and  shows  the  coalescing  of  the  water 
bubbles,  which  causes  the  irregular  shape  of  the  large  bubbles. 


ALEX.    W.    MCCOY,    H.    R.    SHIDEL   AND    E.    A.    TRAGEE  435 

The  surface  tension  of  an  oil-water  contact  makes  it  necessary  for 
the  water  bubbles  to  be  very  small  in  order  to  have  permanent  B.  S. 
If  the  water  bubbles  are  large,  say  1  mm.  in  diameter,  the  masses  of 
water  in  two  such  bubbles  have  sufficient  attraction  for  each  other  and 


FIG.  7. — DIFFERENT  SIZES  OF  .BUBBLES.      X  200  ± . 


FIG.  8. — PARTLY  EMULSIFIED  OIL.      X  450. 

sufficient  force,  in  case  of  an  impact,  to  break  the  film  of  oil  surrounding 
them  and  thus  make  a  larger  water  bubble.  As  this  process  repeats  itself 
and  the  bubbles  increase  in  size,  their  weight  will  cause  them  to  settle 
through  the  B.  S.  until  the  water  collects  below  the  emulsion.  Or  an 


436  INVESTIGATIONS    CONCERNING   OIL-WATER   EMULSION 

increase  in  the  temperature  may  cause  sufficient  expansion  to  break 
the  oil  film;  if  the  bubble  at  this  time  is  in  contact  with  the  container 
or  a  water  layer  below  the  B.  S.,  the  water  in  the  bubble  will  either 
join  that  below  it  or  will  adhere  to  the  container.  If  it  remains  attached 
to  the  side  of  the  container,  the  water  from  other  large  bubbles  may 
be  added  to  it  until  the  large  bubble  so  formed  settles  to  the  bottom. 

In  the  case  of  very  small  water  bubbles,  the  force  of  attraction  upon 
impact  is  not  sufficient  for  the  water  to  break  the  oil  film,  neither  will 
an  increase  in  the  temperature  cause  sufficient  expansion  to  rupture  this 
film.  It  is  a  simple  matter  to  join  two  large  water  bubbles  together  by 
puncturing  the  oil  films  surrounding  them  with  a  needle;  but  it  is  prac- 
tically impossible  to  join  two  small  water  bubbles,  say  0.005  mm.  in 


FIG.  9. — PHOTOMICROGRAPH  OF  B.  s.  WHILE  DRYING.     X  450. 

diameter,  by  any  amount  of  patience  or  skill.  Such  small  bubbles  may 
be  subjected  to  rather  violent  impacts  and  the  tendency  is  to  break 
into  even  smaller  bubbles,  rather  than  to  coalesce. 

In  a  recent  article  by  Harkins,  Davies,  and  Clark,1  it  is  stated  that 
"for  the  emulsoid  particle 'to  be  stable,  the  molecules  which  make  the 
transition  from  the  interior  of  the  drop  to  the  dispersion  medium,  or  the 
molecules  of  the  'film'  should  fit  the  curvature  of  the  drop.  From  this 
standpoint,  the  surface  tension  of  very  small  drops  is  a  function  of  the 
curvature  of  the  surface."  Their  studies  have  suggested  that  small 
drops  in  an  emulsion  tend  to  be  stable  only  when  the  size  of  the  drop  is 
such  that  the  molecules  in  the  surface  film  fit  the  curvature  of  the  sur- 

1  W.  D.  Harkins,  E.  C.  H.  Davies,  G.  L.  Clark :  Orientation  of  Molecules  in  the  Sur- 
faces of  Liquids,  etc.  Jnl.  Amer.  Chem.  Soc.  (April,  1917)  39,  541-596. 


ALEX.    W.    MCCOY;    H.    R.    SHIDEL   AND   E.    A.    TRAGER  437 

face.  There  may  be  more  than  one  size  of  bubble  in  which  the  number 
of  molecules  in  the  surface  fit  the  curvature  of  the  drop.  This  tendency 
for  the  water  bubbles  in  B.  S.  to  arrange  themselves  in  definite  sizes  is 
clearly  seen  in  Figs.  1,  3, 7,  and  8. 

PHYSICO-CHEMICAL  PROPERTIES  OF  EMULSIFIED  OIL 

The  physico-chemical  properties  of  emulsified  oil  are  quite  variable, 
and  each  sample  is  more  or  less  of  an  individual  problem.  The  color 
that  is  most  common  is  a  dark,  reddish  brown,  although  any  color  from 
yellowish  or  greenish  to  gray  or  nearly  black  may  be  found.  The  darker 
colors  generally  contain  more  suspended  matter. 

CLASSES  OF  EMULSIFIED  OIL 

The  permanency  of  emulsified  oil  may  be  used  as  a  basis  for  divi- 
sion into  two  classes:  Temporarily  emulsified  oil  and  permanently  emul- 
sified oil.  The  two  classes  cannot  be  separated  by  their  appearance. 
This  fact  was  brought  out  by  two  sets  of  samples  sent  to  the  laboratory. 
When  the  first  set  was  opened,  the  glass  jars  appeared  to  contain  about 
one-third  water  and  two-thirds  crude  oil.  The  sampler's  attention  was 
called  to  this  fact,  but  he  insisted  that  the  samples  were  "the  best  look- 
ing B.  S."  he  had  ever  seen.  A  second  set  came  at  a  later  date  and  about 
half  of  these  had  no  microscopic  resemblance  to  B.  S.  when  they  reached 
the  laboratory.  The  oil  from  these  samples  was  examined  under  the 
microscope,  and  it  was  found  that  there  were  water  bubbles  present,  but 
they  were  spaced  about  ten  to  twenty  times  their  diameter  apart.  There 
were  practically  no  very  small  water  bubbles  present,  which  indicates 
that  this  material  was  not  subjected  to  as  violent  treatment  as  is  the 
case  with  permanent  B.  S.  Investigations  in  the  laboratory  demon- 
strated that  oil  emulsified  by  a  minimum  amount  of  agitation  will  mostly 
settle  out  in  from  one  to  three  days.  Of  course  there  will  be  small 
water  bubbles  present  in  the  apparently  good  crude  oil  remaining,  but 
the  percentage  will  be  low. 

Permanently  Emulsified  Oil 

Permanently  emulsified  oil  will  stand  indefinitely  and  the  amount 
of  settling  out  is  negligible.  This  oil  is  somewhat  more  viscous  than 
"fresh"  temporarily  emulsified  oil,  and  does  not  contain  as  many  large 
globules  of  water,  but  otherwise  the  oils  appear  similar  to  the  unaided 
eye.  The  specific  gravity  of  emulsified  oil  falls  within  rather  narrow 
limits,  0.95  to  0.995,  although  the  average  is  about  0.96  (15.8°  B6). 
The  oil  that  separated  from  temporarily  emulsified  oil  from  Augusta 
had  an  average  specific  gravity  of  0.86  (32. 8°  Be).  The  specific  gravity 
of  the  Augusta  crude  oil  used  in  the  laboratory  was  0.849  (34.0°  Be). 


438  INVESTIGATIONS   CONCERNING   OIL-WATER   EMULSION 

Permanently  emulsified  oil  has  a  very  high  viscosity.  At  room  tem- 
peratures there  are  all  gradations  from  a  thick  syrupy  consistency  to  a 
near-solid.  In  many  samples  a  hydrometer  placed  upon  the  surface 
will  remain  there  indefinitely.  Heat  rapidly  reduces  this  viscosity. 
A  sample  of  the  most  viscous  oil,  when  heated  to  122°  F.  (50°  C.),  will 
readily  drop  from  a  glass  rod.  At  167°  F.  (75°  C.),  it  has  the  consistency 
of  a  thin  syrup,  and  at  or  near  its  boiling  point,  about  190.4°  F.  (88°  C.), 
it  is  almost  as  mobile  as  water. 

Groups  of  Permanently  Emulsified  Oil 

In  addition  to  lowering  the  viscosity,  heat  also  divides  permanent 
B.  S.  into  two  groups.  In  the  first  group,  the  B.  S.  separates  into  water 
and  oil  shortly  after  it  has  been  heated  to  the  boiling  point,  the  change 
taking  place  rather  suddenly.  Several  degrees  below  the  boiling  point 
there  is  no  apparent  change  in  the  appearance  of  the  sample,  but  as  soon 
as  this  temperature  is  reached  the  water  settles  rapidly. 

Samples  belonging  to  the  second  group  may  be  heated  to  221°  F. 
(105°  C.)  and  held  at  this  temperature  until  all  the  water  and  part  of  the 
oil  have  been  distilled  over,  and  at  no  time  will  there  be  any  signs  of 
separation  of  the  oil  and  water  in  the  still.  However,  in  some  of  the 
samples  the  water  and  oil  did  separate,  on  standing  from  24  to  48  hr., 
after  being  heated  for  1  hr.  at  221°  F.  To  heat  above  this  temperature 
in  an  open  vessel  is  impossible  under  ordinary  conditions,  for  the  material 
begins  to  froth  and  boil  vigorously  between  221°  F.  and  230°  F. 

The  size  and  number  of  the  water  bubbles  in  these  two  groups  of  B.  S. 
is  approximately  the  same,  but  just  what  is  the  cause  of  this  marked 
difference  in  behavior  is  not  fully  understood.  However,  the  gravity 
of  the  oil  from  which  the  B.  S.  was  made,  and  the  per  cent,  of  foreign 
material  present,  appear  to  be  the  factors  that  control  this  behavior. 

AMOUNT  OF  WATER  IN  B.  S. 

It  is  the  common  belief  among  practical  men  in  the  Mid-Continent 
field  that  B.  S.  may  contain  from  1  to  99  per  cent,  water.  If  an  entire 
pipeline  run  that  contains  water  is  all  termed  B.  S.,  this  statement  may 
be  true;  but  if  we  limit  B.  S.  to  that  emulsified  product  which  is  com- 
monly recognized  to  be  unfit  for  the  refinery  without  a  preliminary  treat- 
ment to  remove  the  water,  this  statement  is  not  true.  On  the  other  hand, 
the  per  cent,  of  water  in  true  B.  S.  is  its  most  constant  factor.  In  all 
types  of  B.  S.,  excepting  temporary,  the  water  content  is  very  nearly  66 
per  cent.  This  fact  was  determined  by  distilling  a  number  of  samples 
of  B.  S.  from  various  sources,  including  samples  that  were  manufactured 
in  the  laboratory.  An  attempt  was  then  made  to  synthesize  B.  S.  in 


ALEX.  W.  McCOY,  H.  R.  SHIDEL  AND  E.  A.  TRACER 


439 


the  laboratory,  hoping  to  learn  what  are  the  controlling  factors  in  its 
formation,  and  more  about  its  properties. 

A  4-oz.  oil-sample  bottle  completely  filled  with  70  per  cent,  water 
and  30  per  cent,  oil2  was  rotated  about  a  center,  at  right  angles  to  its 
length,  at  a  speed  of  900  r.p.m.  for  about  10  min.;  at  the  end  of  this  time 
there  were  no  signs  of  emulsification.  The  bottle  was  again  rotated, 
this  time  for  2J^  hr.,  but  no  emulsification  took  place.  The  bottle  was 


FIG.  10. — SIMPLE  APPARATUS  IOR  DEMONSTRATING  EMULSIFICATION. 

next  placed  on  an  automatic  shaker  and  shaken  for  3  hr.,  but  no  change 
occurred.  Part  of  the  oil  and  water  was  then  removed  and  about  10 
per  cent,  of  fine  sand  was  placed  in  the  bottle,  which  was  rotated  for  3 
hr.,  and  then  shaken  for  3  hr.,  but  negative  results  were  obtained  as 
before. 

This  experiment  was  repeated  using  70  per  cent,  water  and  30  per 
cent,  oil,  but  having  the  bottle  only  three-fourths  full;  hi  just  a  few  min- 
utes after  the  bottle  was  placed  upon  the  shaking  device  emulsification 


2  Augusta  crude  oil  was  used  in  all  laboratory  experiments. 


440  INVESTIGATIONS   CONCERNING    OIL-WATER   EMULSION 

began  to  take  place.  In  30  min.  the  entire  contents  of  the  bottle  had 
been  converted  into  permanent  B.  S.  These  experiments  indicate  that 
air  or  voids  in  the  fluid,  in  addition  to  water  and  oil,  are  necessary  in 
the  emulsification  of  oil,  the  air  acting  as  a  catalytic  agent. 

A  simple  laboratory  apparatus  for  demonstrating  emulsification, 
under  conditions  more  similar  to  those  existing  at  the  time  a  well  is 
being  pumped,  is  shown  in  Fig.  10.  One  tube  A  passes  into  a  beaker 
containing  oil,  another  tube  B  into  a  beaker  of  water,  while  air  could  be 
introduced  at  will  through  a  third  C.  The  graduated  cy Under  is  used 
as  a  reservoir  and  the  "well"  is  pumped  by  a  vacuum  attached  to  tube 
D.  Water  and  oil  were  first  drawn  through  the  column  of  sand;  the 
percentages  of  each  were  varied,  but  under  no  conditions  was  more  than 
1  per  cent,  of  B.  S.  formed.  But  when  water,  oil,  and  ah*  were  drawn 
through  the  sand,  immediately  the  percentages  of  B.  S.  formed  began  to 
rise.  The  "well"  was  pumped  at  different  rates  of  speed  and  variable 
amounts  of  air  were  introduced;  the  amount  of  B.  S.  formed  ranged  from 
1  to  15  per  cent. 

If,  instead  of  using  fine  sand,  pebbles,  about  0.25  in.  (6.35  mm.)  in 
diameter  or  larger,  are  used  and  air  under  a  low  pressure  is  introduced 
through  a  large  opening,  0.1875  in.  (4.7  mm.)  diameter  or  larger,  the 
amount  of  B.  S.  formed  will  be  very  small.  For  under  these  conditions 
most  of  the  water  and  oil  pass  through  the  gravel  without  being  broken 
into  bubbles  small  enough  to  remain  permanently  emulsified. 

Since,  to  permanently  emulsify  oil,  it  is  only  necessary  to  break  the 
water  present  into  very  small  bubbles  and  then  surround  these  small 
water  bubbles  with  a  film  of  oil  before  they  have  an  opportunity  to  coa- 
lesce, B.  S.  can  be  made  by  blowing  air  bubbles  through  water  and  oil 
in  a  cylinder.  If  67  c.c.  of  water  and  23  c.c.  of  oil  are  placed  in  a  100  c.c. 
graduated  cylinder,  and  air,  under  5  to  8  Ib.  pressures  coming  from  an 
opening  about  0.5  mm.  in  diameter,  is  allowed  to  bubble  through  the 
column  of  liquid,  the  entire  contents  of  the  cylinder  will  be  converted 
into  permanent  B.  S.  within  3  to  5  min.  The  amount  of  B.  S.  formed, 
up  to  a  limiting  per  cent.,  will  depend  on  the  percentages  of  water  and 
oil  present. 

Table  1  gives  the  results  of  such  an  experiment,  using  various  com- 
binations of  oil  and  water,  and  agitating  for  5  min.  with  a  current  of  air 
under  5  Ib.  pressure.  The  first  readings  were  taken  after  standing  for 
30  min.,  the  second  after  standing  a  week. 

The  settling  out  shown  in  the  table  is  due  mostly  to  large  globules  of 
water  trapped  in  the  B.  S.  that  later  worked  their  way  down  through 
the  B.  S.  to  the  water  level;  and  to  small  amounts  of  oil  rising  to  the  top 
of  the  B.  S.  B.  S.  may  also  be  made  by  this  method  if  natural  gas  or 
steam  is  substituted  for  the  air. 


ALEX.  W.  McCOY,  H.  K.  SHIDEL  AND  E.  A.  TBAGER 


441 


TABLE  1. — Percentage  of  B.  S.  Formed  Upon  Five-Minute  Agitation, 
Using  Various  Combinations  of  Oil  and  Water 


Water,  Per  Cent. 

Oil,  Per  Cent. 

B.  S.  After  Standing 
30  Minutes,  Per  Cent. 

B.  S.  After  Standing  One 
Week,  Per  Cent. 

90 

10 

3 

4 

80 

20 

32 

16 

75 

25 

62 

22 

70 

30 

86 

66 

65 

35 

82 

70 

60 

40 

90 

58 

50 

50 

80 

60 

40 

60 

66 

50 

30 

70 

56 

38 

20 

80 

34 

24 

10 

90 

18 

18 

0 

100 

0 

0 

Table  2  gives  the  distillation  results  from  three  samples  of  B.  S. 
No.  1  was  taken  at  a  well,  No.  2  was  received  from  a  steaming  plant,  and 
No.  3  is  a  composite  of  the  samples  obtained  from  the  experiment  shown  hi 
Table  1.  In  these  experiments,  the  material  was  heated  from  6  to  8  hr. 
to  obtain  all  the  water.  The  residue  is  composed  of  all  the  oil  boiling 
over  "105°  C.,  fine  particles  of  shale,  sand,  and  limestone,  and  a  few 
crystals  of  salt  and  pyrite,  flakes  of  mica,  etc. 

TABLE  2. — Distillation  Results 


Number  of  Sample 

Oil  Distilling  below 
105°  C.f  *  Per  Cent. 

Water,  Per  Cent. 

Residue  and  Air, 
Per  Cent. 

1 

10.5 

66.0 

24.5 

2 

10.0 

66.5 

24.5 

3 

6.3 

66.0 

21.0 

7  .  0  air  and  loss. 

*  Distillation  runs  under  105°  C.  to  determine  the  per  cent,  of  water  in  B.  S. 


FIELD  INVESTIGATION    ON  EMULSIFIED  OIL 

Oil  accumulated  at  the  bottom  of  a  well  enters  the  mechanical  parts 
through  the  perforated  tubing.  It  is  drawn,  through  the  standing  valve, 
into  the  working  barrel,  when  the  ball  is  raised  from  its  seat,  by  the 
vacuum  created  in  the  up- stroke.  On  the  down-stroke,  the  working 
valve  opens  and  allows  the  fluid  to  pass  into  the  tubing.  It  is  then  lifted 
about  3  ft.  by  each  successive  up-stroke  until  it  reaches  the  surface  and 
flows  from  the  well  through  a  lead  line  to  a  receiving  tank  (see  Fig.  11). 


442 


INVESTIGATIONS   CONCERNING   OIL-WATER   EMULSION 


Bleeder  for  Sampling 


Adjuster 
Adjuster  Board 


Walking  Beam 


Polish  Bod 


Li    Stuffing-box 


Lead  Line  to  Tauk 


Lead  Lines  to  Gas  or  Oil 
Big  Floor 


Tubing 


Sucker  Bod 
Working  Barrel 

Working  Valve 
Standing  Valve 

! : 

Perforation 
Anchor 


FIG.  ll. — DIAGRAM  OF  WORKING  PARTS  OP  PRODUCING  OIL  WELL. 


ALEX.   W.   MCCOY,    H.    R.    SHIDEL   AND    E.    A.    TRAGER 


443 


When  a  sample  is  to  be  taken,  the  check  valve  on  the  tank  lead  line  is 
closed  so  that  the  fluid  coming  from  the  tubing  is  not  affected  by  the  back 
pressure  from  the  tank.  The  valve  on  the  short  lead  line  is  opened  and 
the  sample  is  caught  in  a  bucket  (see  Fig.  12)  and  allowed  to  settle 
for  about  30  sec.  The  vertical  cylinder  is  then  placed  in  the  guides  of  the 
bucket,  separating  a  representative  column  measuring  about  90  or  100 
c.c.  of  fluid,  which  is  drawn  off  through  the  small  valve  in  the  bottom  of  the 
bucket.  The  sample  is  then  centrifuged,  the  oil,  B.  S.,  and  water  separat- 
ing out.  By  plotting  the  results  of  such  samples,  taken  every  10  min., 


FIG.  12. — DIAGRAM  OF  SAMPLE  BUCKET. 

many  irregular  conditions  have  been  noted.  All  producing  oil  wells  do 
not  perform  in  the  same  manner;  some  of  the  different  conditions  are 
shown  by  the  accompanying  charts. 

Fig.  13  shows  the  graph  of  a  well  producing  a  high  percentage  of  water; 
there  is  no  emulsion  in  the  fluid.  The  oil  and  water  remains  in  about  the 
same  ratio  over  a  period  of  8  hr.  The  well  was  pumping  about  200  bbl. 
per  day  when  this  test  was  made.  Fig.  14  also  shows  a  graph  of  a  well 
making  a  large  percentage  of  water;  there  is,  however,  a  small  percentage 
of  emulsion  plotted  through  the  entire  time  of  the  test.  Fig.  15  represents 
a  well  producing  a  large  percentage  of  water  and  a  comparatively  large 
percentage  of  B.  S. 

Fig.  16  shows  the  graph  of  a  well  producing  a  low  percentage  of  water, 
a  high  percentage  of  oil,  and  a  comparatively  high  percentage  of  emulsion. 


444 


INVESTIGATIONS   CONCERNING   OIL-WATER   EMULSION 


Fig.  17  illustrates  a  well  that  has  just  pumped-off  a  head  of  water,  after 
which  the  percentage  of  oil  suddenly  rose  and  remained  about  the  same  for 
some  time  then  gradually  decreased.  At  the  time  of  the  increase  in  the 


IOC 


70 


Sso 

£40 


30 


10 


\ 


/UVA 


Oil 
B.8. 


LEGEND 


Water 


9:00 


5:00 


10:00  11:00  12:00  1:00  2:00  3:00  4:00 

AJVI.  Time  PJVf. 

FIG.  13.  —  GRAPH  OF  WELL  PRODUCING  HIGH  PERCENTAGE  OP  WATER. 


6:00 


1UU 
90 
80 
70 
60 
50 
40 
20 
20 
10 
0 

fiafi 

AX\ 

a^-a 

P*±A 

^0.^,^      0-J 

'N       0^-^ 

C>-0 

a-" 

V         \ 

w 

V 

V 

LEGEND 
on 

B  S 

\Vutur  -— 

a 

>°S»       _y 

_  /s 

yA               0 

NrV 

w 

V^ 

\M^^ 

v^W 

r^o^V 

V 

O--O-O-0-O-C 

^—.O-O^-^-O-" 

•-O.Q-O-O-O-I 

-o-o-o-o—  o-< 

--O-O^Q—  O-O-( 

o-o  o 

8.-00 


11:00 


4:00 


5:00 


12:00          1:00  2:00  3:00 

AJVI.  Time  P.M. 

FIG.  14. — GRAPH  OF  WELL  PRODUCING  LARGE  PERCENTAGE  OF  WATER  AND  SMALL 

PERCENTAGE  OF  EMULSION. 

percentage  of  oil,  the  percentage  of  B.  S.  rose  and  continued  to  increase 
at  about  the  same  rate  as  the  oil  dropped  later.  The  fluid  came  from 
the  tubing  much  more  slowly  as  pumping  progressed.  Fig.  18  shows  a 


ALEX.   W.   MCCOY,   H.   B.   SHIDEL   AND   E.   A.   TEAGER 


445 


greater  increase  in  the  percentage  of  B.  S.  The  amount  of  fluid  produced 
during  the  last  hour  was  25  per  cent,  of  the  amount  pumped  during  the 
first  hour  of  the  test. 


100 

80 
70 
60 
0    50 

% 

30 
20 
10 

°S 

FIG.  ] 

100 
90 
80 
70 

60 

v 
U  50 

30 
20 
10 

0 

8 

on    LEGEND 

B  8 
Water  

p 

K 

J? 
/\ 

A, 

v 

,  n   ' 

\  /    \/ 

'  V    N 

-\  A 

?r 

IS 

,\  /-A 

'  '  '-, 

H 

• 

'  V 

v  \ 

f 

'4        s> 

ts 

\ 

a/\/>~' 

WW 

^v^\ 

yv-^ 

^^v 

S^s^ 

^V^1 

H^V 

^52- 

f 

/  \  '* 

X\  /I 

\  A 

I  A;/ 

5 

,"   / 

'vx\ 

«  ^; 

^  ' 

i  •  v 

"v            V/ 

vx 

9 

V 

'  W 

V 

^'\' 

:00           9:00           10:00          11.00           12:00           1:00            2:00            3:00            4:00            5:0 
A.M.                                      Time                                         P.M. 

15.  —  GRAPH  OP  WELL  PRODUCING  LARGE  PERCENTAGE  OP  WATER  AND  COMPARE 
TIVELY  LARGE  PERCENTAGE  OP  B.  S. 

sAA< 

&.,., 

^-^oV^ 

V-o^     />-( 

A^/^ 

-°^>^o-. 

sA-A 

—A 

JHV^, 

Y 

LEGEND 
Oil        

A 

A/V 

!Z± 

r^^v 

7^ 

NS>^ 

A/V 

k    p-'*x'0 

V°-«"0-o-., 

_.o-.o--o~c-o~i 

^o-o-o-o--0-' 

^-O-O-.o-o.o.., 

ro-o~a.(rO't 

*i4^ 

"••o-o-o-o-'O-' 

h-cx  o-o-o 

30            9:30            10:30           11:30          12:00            1:30             2:30             3:30            4:30            5:3 
AM.                                              Time                                            P.M. 

FIG.  16. — GRAPH  OP  WELL  PRODUCING  LOW  PERCENTAGE  OP  WATER,  HIGH  PERCENTAGE 
OP  OIL,  AND  COMPARATIVELY  HIGH  PERCENTAGE  OP  EMULSION. 

Fig.  19  represents  the  behavior  of  a  well  pumping  all  water  for  several 
hours;  after  this  was  exhausted  the  percentage  of  oil  increased  rapidly. 
The  water  pumped  during  the  early  hours  of  the  test  was  the  water  that 


446 


INVESTIGATIONS    CONCERNING   OIL-WATER   EMULSION 


separated  out  of  the  fluid  behind  the  tubing.  As  the  head  of  fluid  was 
reduced,  the  oil  finally  came  into  the  tubing.  The  percentage  of  B.  S. 
was  practically  nil. 


10U 
90 
80 
70 
60 

1 

0     50 
*Ji 

30 

20 
10 
'     0 

•     s 
F 

100 

90 
80 
70 
60 
<J    50 
*    46 
30 
26 

10 

0 
( 

o' 

^ 

n 

«„       LEGEND 

Water    

\ 

^ 

^^^ 

Sx—  N^ 

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1 

/ 

\ 
\ 

^^^ 

/»>o^>-o-^ 

sf^    P-* 

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^ 

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s 

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.... 

-0-O--O--O-O-- 

:00            9:00           10:00            11:00           12:00            1:00             2:00            8:00            4:00            5:0 
AM.                                        Time                                       PM. 

IG.  17.  —  GRAPH  OF  WELL  THAT  HAS  JUST  PUMPED  OFF  HEAD  OF  WATER. 

A 

,A, 

\ 

01,     LEGEND             I 

cr 

1 

^^—\ 

~^v 

Water--    -   j 

ro^-o^ 

^v. 

V     -fc_ 

, 

W^ 

\^ 

^-0 

^ 

/ 

^f 

s^^ 

s^- 

S? 

Yu     S 

-v^. 

j^o-o-^-o-o-- 

f«"0--0"0"0- 

^^o-svx,'0- 

r 

:00            £:00           10:00            11:00           12:00             1:00             2:00           3:00             4:00           5:0 

AJV1.  Time  P.M. 

FIG.  18. — SIMILAR  TO  FIG.  17  BUT  SHOWING  GREATER  INCREASE  IN  PERCENTAGE  OF  B.  s. 

Fig.  20  is  the  graph  of  a  well  that  pumped  only  6  hr.  during  the  day. 
The  fluid  in  the  tubing  was  composed  entirely  of  oil  and  B.  S.,  which  did 
not  separate  out.  The  high  percentage  of  water  following  was  probably 


ALEX.    W.    MCCOY,    H.    R.    SHIDEL   AND    E.    A.   TRAGER 


447 


the  accumulation  of  water  behind  the  tubing,  which  passed  into  the  hole 
during  the  shutdown.  When  the  water  was  about  exhausted,  the  per- 
centages of  oil  and  B.  S.  were  about  the  same  as  when  the  well  was  started. 


100 
00 

so 

70 

40 
30 
20 

i 
.,  —  i  

oil     LEGEND 

M~ 

"     B.8. 
Water   

1   0 

'  W  * 

GTE 

1  t\h 

i  pa 

K 

M 

/  , 

1 

0 

8 

in  2 

^ 
o-o-o-o-< 

:00          9:00            10:00          11:00           12:00            1:00         2:00               3:00             4:00            5:0 
AJVI.                                  Time                                      PJVI. 

FIG.  19. — BEHAVIOR  OP  WELL  PUMPING  ALL  WATER  FOR  SEVERAL  HOURS. 


aft 

Oil 

LEGEND 

/ 

B.8. 

Water 

—           — 

80 
70 

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| 

J 

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00           9: 

00           10 

00          11: 

00 

12 

.00             1: 

90           2:( 

)«             3: 

)0           4: 

00           5.-OC 

AJVI.  Time  PJVI. 

FIG.  20. — GRAPH  OP  WELL  PUMPED  6  HR.  A  DAY. 


A  well  of  this  order,  when  pumping  continually,  would  not  show  such  an 
erratic  condition,  as  there  would  be  no  chance  for  a  large  head  of  water  to 
collect  in  the  hole. 


448 


INVESTIGATIONS  CONCERNING   OIL-WATER   EMULSION 


Fig.  21  shows  the  action  of  a  well  producing  an  extremely  high  per- 
centage of  B.  S.  with  small  percentages  of  oil  and  water.  The  well  was 
shut  down  for  3%  hr.  When  pumping  was  started  again,  it  first  pro- 


100 

j|L4 

Vv 

I 
\ 

| 

A 

f^<J    1 

Ki 

^'\ 

80 

\ 

V 

j 

^ 

70 

1 

\ 

j, 

Shut 

down 

1                     j 

60  / 

g    ' 

r  i     Ptfl 

1 

O    50 

• 

rv. 

40 

30 
a 

20  ri 
10 

0 

9 

FIG.  \ 

100 
90 
80 
70 

60 

c 

V 

0    50 

1 

30 
20 
10 

or 

on    LEGEND 

B.S. 
"Water 



— 

0 

1 

\ 

1           1 

r 

/V^ 

,-\\ 

r-/' 

^  »*s 

Vy 

\r 

v\ 

/ 

/     "^ 

:30            10:30           11:30           12:30            1:30            2:30            S:30             4:30            5:30           6:30 
AM.                                            Time                              P.M. 

51.  —  GRAPH  OP  WELL  PRODUCING  EXTREMELY  HIGH  PERCENTAGE  OP  B.  s.  AND 

SMALL    PERCENTAGES   OP   OIL   AND   WATER. 

LEGEND 

***A 

^V<v   . 

Water  - 

l 

1 

AA 

/\       Not 

-Well  shi 
6  A.M. 

t  down  frot 
>f  Night  Pre 

9  P.M.  to 
ceding 

1 

1 

V 

0 

£ 

II 

S^ 

tyZZl 

*°-\j^ 

^A 

o 

T~ 

9 

o 

Q 

V 

8 

a 

/A/ 

•vy\ 

^A^ 

> 

11 

i  ? 

\    (\    s 

/" 

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ts 

^Av-^^ 

l\K 

A£ 

^•&'1  A 

a.»~\  r 

AV 

K£A 

SF               f> 

0-^.^.0-0-* 

o-o-^-o-* 

X  * 

[/» 

tf 

u 

6 

o 

0 

:00           8:00            9:00           10:00           11:00          12:00           1:00           2:00             3:00           4:00 

A.M.  Time  P.M. 

FIG.  22. — GRAPH  OP  WELL  PUMPING  LARGE  AMOUNT  OP  FLUID  AT  START. 

duced  the  same  percentage  of  B.  S.  as  before.  Within  40  min.,  though, 
the  high  percentage  of  B.  S.  dropped  to  nothing  with  a  great  increase  of 
water.  At  this  time,  the  percentage  of  oil  increased  some.  In  2  hr. 


ALEX.   W.    MCCOY,    H.   R.   SHIDEL  AND   E.   A.   TRACER 


449 


the  water  was  exhausted  and  the  well  started  to  operate  with  a  more  regu- 
lar flow.  The  influx  of  water  was  due  to  the  accumulation  of  water 
behind  the  tubing,  during  the  shutdown. 


^^ 


*•*' 


UMOQ   inqg    H 


a.S'S 

i?*J 


°°" 

a* 


^S>2 
I  I  I 
5  * 

i.f 

IP 

sill 

5  a>OHO. 


"--Q.- . 


anijdmnj 


§      8 


§ 


Fig.  22  shows  a  well  that  was  pumping  a  large  amount  of  fluid  at  the 
start,  the  greater  percentage  of  which  was  oil.  As  pumping  continued, 
the  percentage  of  oil  decreased  and  that  of  the  B.  S.  increased.  There  was 
a  perceptible  rise  in  the  percentage  of  water  too.  At  the  end  of  the  test, 


29, 


450  INVESTIGATIONS   CONCERNING   OIL-WATER   EMULSION 

the  well  was  producing  about  one-third  the  amount  of  fluid  that  it  did  at 
first. 

Fig.  23  illustrates  the  performance  of  a  well  from  the  time  the  pump 
was  started  until  it  was  stopped.  At  first,  the  well  produced  a  good  per- 
centage of  oil,  which  rapidly  decreased  to  nothing.  This  percentage 
represents  the  oil  that  had  settled  in  the  tubing  during  the  12-hr,  shut- 
down previous  to  starting.  After  this  was  pumped  out,  the  well  produced 
nothing  but  water  for  several  hours;  oil  was  then  noted.  By  this  time, 
the  water  in  the  tubing,  behind  the  tubing,  and  some  that  had  probably 
been  backed  up  in  the  oil  sand  had  been  pumped  off.  The  oil  that  had 
separated  out  to  the  top  of  the  water  outside  of  the  tubing  was  being 
pumped.  Less  fluid  was  pumped  at  this  time  than  when  only  water  was 
being  produced.  During  the  next  2  hr.,  the  well  was  producing  at  about 
the  same  rate.  Undoubtedly,  some  of  this  fluid  was  partly  accumulated 
during  the  shutdown  and  partly  coming  into  the  well  during  the  pumping. 
After  this,  a  decided  drop  in  the  amount  of  production  was  noted,  with  a 
decrease  in  percentage  of  water  and  an  increase  in  the  percentage  of  oil. 
The  fluid  from  this  time  on  was  probably  coming  direct  from  the  sand. 

Fig.  24  shows  the  performance  of  an  oil  well  over  a  period  of  33  hr. 
During  that  time  several  experiments  were  tried  and  the  results  noted. 
At  9:30  A.M.,  the  pump  was  started,  showing  a  high  percentage  of  oil, 
which  dropped  materially  within  10  min.;  this  was  the  oil  that  had  settled 
out  during  the  shutdown.  The  well  produced  a  large  percentage  of  B.  S. 
for  1J^  hr.  From  11:10  A.M.  to  11:30  A.M.,  there  was  a  large  increase 
in  the  percentage  of  oil  followed  by  a  sudden  and  greater  drop  than  before. 
This  was  the  oil  that  had  risen  to  the  top  of  the  fluid  around  the  tubing 
during  the  period  of  shutdown.  From  12 : 20  P.M.  until  6 : 20  P.M.,  the  well 
was  pumping  about  as  fast  as  oil  and  water  were  coming  from  sand;  gradu- 
ally a  big  increase  of  B.  S.  was  noted.  From  8 : 30  P.M.  until  11 : 30  P.M.,  the 
well  was  shut  down .  When  it  started  to  pump  agai»,  the  first  test  reported 
a  high  percentage  of  oil,  which  immediately  dropped  and  the  well  produced 
fluid  in  about  the  same  percentages  as  that  before  the  shutdown  until 
1 : 50  A.M.  At  this  time  an  increase  in  the  percentage  of  oil  was  noted, 
followed  immediately  by  the  correspondingly  large  increase  of  water. 

The  fluctuations  following  are  the  results  of  quantities  of  oil  and  water 
getting  into  the  working  barrel  in  separate  bodies.  From  4  until  8 
o'clock,  the  well  was  operating  with  about  an  average  percentage  of  oil, 
B.  S.  and  water.  The  well  was  shut  down  from  8:40  A.M.  until  9:20 
A.M.  and  from  then  until  11 :20  A.M.,  it  operated  about  the  same  as  it  did 
from  4  A.M.  until  8  A.M.  At  this  time  there  was  a  noted  increase  of  water. 
The  fluctuation  of  oil  and  water  was  due  to  the  separation  around  the 
tubing  during  the  shutdown.  From  12:10  until  5:30,  the  well  operated 
with  a  regular,  or  normal,  flow. 


ALEX.    W.    MCCOY,    H.    R.   SHIDEL   AND   E.    A.    TRAGER 


451 


8     g 


8   8    s 


00^, 


452  INVESTIGATIONS   CONCERNING  OIL-WATER  EMULSION 

An  interesting  feature  of  the  curve  is  the  fact  that  after  the  well  had 
been  standing  idle  for  a  while  it  produced  with  a  regular  and  then  an 
irregular  flow.  The  average  production  of  the  well  was  about  40  per 
cent,  oil,  50  per  cent.  B.  S.,  and  10  per  cent,  water.  This  mixture  in  the 
tubing  did  not  settle  out  readily  during  the  shutdown  so  that  when  the 
well  started  producing  again  it  pumped  approximately  this  ratio  of  fluid 
for  the  first  2  hr.,  clearing  the  tubing  of  the  fluid  left  there  during  the  idle 
period.  While  the  well  was  not  operating,  oil  and  water  filled  up  behind 
the  tubing  from  the  sand,  which  was  pumped  largely  as  clear  oil  and  water 
with  comparatively  little  B.  S.  after  the  fluid  in  the  tubing  was  exhausted. 
When  the  accumulated  head  behind  the  tubing  was  reduced,  the  normal 
production  returned.  This  series  of  conditions  followed  each  shutdown. 
The  B.  S.  content  is  only  important  when  there  is  no  large  head  of  fluid 
behind  the  tubing.  As  shown  by  the  graph,  the  B.  S.  content  increased 
materially  from  6  until  8  P.M.,  after  the  normal  flow  had  gone  on  for  5  hr. 
Pumping  was  no  doubt  going  on  at  a  faster  rate  than  the  production 
from  the  sand  so  that  gas,  air,  or  voids  in  the  fluid  column  were  admitted 
and  the  oil  emulsified  to  a  greater  amount. 

Referring  again  to  Fig.  23,  the  following  computation  was  made  to 
determine  the  amount  of  fluid  at  different  times  during  the  test.  During 
the  first  hour  (10: 10  to  11 : 10  A.M.)  of  pumping  the  average  of  oil  content 
was  83  per  cent.  The  beam  was  making  15  strokes  per  minute  and  it 
took  two  strokes  to  fill  a  bucket  of  7  qt.  (6.61.)  capacity.  Consequently, 
this  is  equal  to  786  gal.  (2975 1.)  per  hour  or  about  18.7  bbl.  per  hour.  If 
the  oil  content  is  83  per  cent,  of  this  fluid,  the  amount  of  oil  pumped  dur- 
ing this  period  is  15.52  bbl.  For  the  next  6J£  hr.,  the  well  produced  prac- 
tically no  oil. 

From  5:20  to  7:20  P.M.,  the  well  was  producing  about  20  per  cent.  oil. 
The  b  earn  wasmaking  15  strokes  per  minute  and  it  took  four  strokes  to 
fill  a  bucket  of  7  qt.  capacity.  This  is  equal  to  393.6  gal.  (1490  1.)  or 
9.37  bbl.  of  fluid  per  hour.  If  the  oil  content  is  20  per  cent,  of  this  fluid, 
the  amount  of  oil  pumped  during  this  period  is  3.75  barrels. 

From  7:20  to  10:00  P.M.,  the  well  was  producing  about  25  per  cent.  oil. 
The  beam  was  making  15  strokes  per  minute  and  it  took  six  strokes  to 
fill  a  bucket  of  7  qt.  capacity.  This  amount  is  equal  to  262.2  gal.  (992  1.) 
or  6.24  bbl.  of  fluid  per  hour.  If  the  oil  content  is  25  per  cent,  of  this 
fluid,  the  amount  of  oil  pumped  during  this  period  is  4.16  barrels. 

The  total  amount  of  oil  produced  is:  15.52  +  3.75  -f  4.16  =  23.43 
bbl.  The  total  amount  of  B.  S.  and  water  produced  is:  115.38  +  14.99 
+  12.48  =  146.04  bbl.  The  total  amount  of  fluid  is:  23.43  +  146.04 
=  169.47  bbl.  During  the  12-hr,  shutdown,  the  oil  and  water  were 
allowed  to  accumulate  in  the  well.  The  tubing  remained  full  of  fluid 
as  it  was  when  pumping  was  started.  The  fluid  entering  the  well  filled 
up  behind  the  tubing. 


ALEX.    W.   MCCOY,    H.    R.    SHIDEL   AND   E.    A.   TBAGER  453 

The  following  computation  shows  the  amount  of  time  required  for  the 
raising  of  the  fluid  at  the  bottom  of  the  well  to  the  top:  Area  of  3-in. 
tubing  is  7.06  sq.  in.  Area  of  %-in.  rods  is  0.44  sq.  in. ;  difference,  6.62  sq. 
in.  The  number  of  cubic  inches  in  1  ft.  of  3-in.  (76-mm.)  tubing  is  equal 
to  6.62  by  12  in.  or  79.44;  then  2.91  ft.  of  3-in.  tubing  contains  1  gal.  of 
fluid.  The  depth  of  the  well,  2425  ft.  (739  m.),  divided  by  2.91  is  equal  to 
the  number  of  gallons  of  fluid  in  the  tubing,  which  is  833.3  gal.  or  19.84  bbl. 
Pumping  at  the  rate  of  18.71  bbl.  per  hour,  the  time  that  it  would  require 

to  empty  the  tubing  would  be  1   '  1  which  is  equal  to  1.06  hr.  or  1  hr. 

lo./ 1 

4  min.    It  will  be  noted  by  the  graph  that  the  big  influx  of  water  came 
in  1  hr.  10  min.  after  the  well  started  to  pump. 

Referring  to  Fig.  24,  the  following  computation  has  been  made  to  show 
the  amount  of  time  required  in  this  well  for  the  raising  of  the  fluid  from 
the  bottom  to  the  top.  The  depth  of  the  well  (2475  ft.)  divided  by  2.91 
is  equal  to  the  number  of  gallons  of  fluid  in  the  tubing,  which  is  850  gal., 
or  20.2  bbl.  Pumping  at  the  rate  of  8.71  bbl.  per  hour,  the  time  required 

20  2 
to  empty  the  tubing  would  be  ^~  which  is  equal  to  2.32  hr.  or  2  hr. 

O.  I  1 

19  min.    The  well  was  pumped  at  the  above  rate  beginning  at  11 : 30  P.M. 
and  the  time  required  for  the  first  big  fluctuation  to  occur  was  2  hr. 

20  min.    These  figures  give  an  idea  of  the  time  required  to  pump  the 
fluid  from  the  tubing  and  the  variation  of  the  same  in  different  wells. 

The  question  naturally  arises  as  to  whether  or  not  the  separation  of  oil 
and  water  while  passing  through  the  tubing  is  sufficient  to  cause  a  dis- 
crepancy in  the  ratios  of  oil  and  water  in  each  unit  volume  as  it  flows  from 
the  bleeder,  and  the  ratio  of  the  fluids  as  they  enter  the  perforations.  In 
other  words,  after  the  well  has  pumped  the  full  column  of  fluid  in  and  be- 
hind the  tubing,  are  the  proportions  of  oil  and  water  at  the  bleeder  the 
same  as  they  are  in  entering  from  the  sand?  The  rate  of  separation  of  oil 
globules  in  a  water  column  depends  on  the  difference  in  the  specific 
gravity  of  the  two  liquids,  the  temperature  of  the  same,  and  the  size 
of  the  globules.  If  the  full  column  of  fluid  is  lifted  2500  ft.  (762  m.)  in  1  or 
2  hr.,  certainly  that  time  is  sufficient  for  considerable  separation  if  the 
fluid  remains  quiet.  However,  it  has  been  noted  by  experiment  that  a 
slight  stirring  will  prevent  any  separation  of  the  fluids,  and  since  the 
rods  are  constantly  flapping  through  the  fluid  column,  it  seems  that  any 
tendency  to  separate  while  pumping  would  be  greatly  if  not  altogether 
reduced.  Moreover,  if  the  water  from  each  unit  volume  should  be  con- 
stantly descending  to  the  next  unit  volume  etc.  all  the  way  down  the 
column,  the  bleeder  would  still  receive  something  of  the  same  ratio, 
only  apparently  at  later  time. 

From  a  number  of  the  curves,  it  will  be  noted  that  after  a  well  has 
been  pumped  for  several  hours,  the  ratios  of  oil,  B.  S.,  and  water  tend  to 


454  INVESTIGATIONS   CONCERNING   OIL-WATER   EMULSION 

remain  nearly  constant,  without  large  or  rapid  fluctuations.  This  may 
continue  for  a  long  time,  only  after  the  fluid  head  behind  the  tubing  has 
been  reduced.  For  that  and  the  above  reasons,  we  have  considered  the 
ratios  at  the  bleeder  when  the  fluid  head  is  once  reduced  to  be  the  same 
as  the  ratios  of  water  and  oil  entering  from  the  sand  and  have  called  this 
the  "normal  flow." 

CONCLUSION 

Permanent  B.  S.  is  an  emulsion  of  very  small  water  bubbles  in  oil 
having  a  diameter  generally  less  than  0.5  mm.  The  oil  may  be  relatively 
clean  or  it  may  contain  variable  amounts  of  suspended  matter.  There  are 
generally  a  few  air  bubbles  present. 

The  behavior  of  B.  S.  on  heating  may  be  used  as  an  economically 
important  basis  for  division  into  two  groups.  In  the  first  group,  the 
water  separates  from  the  oil  rapidly  with  a  small  amount  of  heating. 
In  the  second  group,  the  water  can  be  removed  only  by  distillation. 

To  form  B.  S.,  it  is  necessary  to  have  present,  in  addition  to  oil  and 
water,  either  air,  a  gas,  or  voids  in  the  continuity  of  the  fluid,  i.e.,  a  break 
in  the  fluid. 

The  percentages  of  oil,  B.  S.,  and  water  vary  in  the  individual  wells; 
each  well  is  a  problem  in  itself. 

A  small  steady  amount  of  B.  S.  is  probably  due  to  bad  valves  and  cups. 
Percentages  of  B.  S.  are  increased  as  the  column  of  fluid  around  the  tubing 
is  exhausted ;  such  a  condition  allows  air  to  enter  the  working  barrel  or  a 
break  to  occur  in  the  column  of  fluid.  This  condition  is  responsible  for 
large  amounts  of  B.  S.  The  bubbles  of  the  different  liquids  and  gases  are 
made  smaller  and  consequently  more  stable  by  the  whipping  of  the  rods. 

The  maximum  efficiency  of  a  pumping  well,  which  is  producing  both 
water  and  oil,  is  obtained  when  the  fluid  level  is  kept  above  the  perforated 
tubing  and  below  the  point  where  the  accumulated  head  of  water  would 
stop  the  flow  of  oil  into  the  hole,  and  when  the  fluid  is  pumped  at  the  same 
rate  that  it  comes  from  the  sand.  Such  conditions  can  only  be  deter- 
mined by  a  special  test  of  the  individual  well. 

DISCUSSION 

A.  W.  AMBROSE,  Washington,  D.  C.— Did  you  make  any  analysis  of 
the  amount  of  emulsion  at  the  well  and  after  you  flowed  it  through  a 
lead  line  to  the  storage  tank? 

E.  A.  TRACER. — B.  S.  can  be  formed  in  passing  through  a  lead  line  by 
the  friction  due  to  the  roughness  of  the  pipe  and  the  irregularities  at  the 
joints. 

R.  W.  MOORE. — Did  you  find  the  percentage  of  water  to  be  limited  to 
the  percentage  of  oil  in  the  emulsion  which  formed? 


DISCUSSION  455 

E.  A.  TRAGER. — Yes,  the  percentage  is  about  67  per  cent,  water  and  23 
per  cent.  oil. 

R.  W.  MOORE. — If  you  added  more  water  would  the  emulsion  be 
permanent? 

E.  A.  TRAGER. — Yes,  it  would  be  permanent,  but  the  excess  water 
would  separate  out. 

THE  CHAIRMAN  (C.  W.  WASHBURNE,  New  York,  N.  Y.). — Did  you 
use  hot  or  cold  water  in  these  experiments? 

E.  A.  TRACER. — It  makes  no  difference  which  is  used.    We  tried  to 
determine  whether  the  composition  of  B.  S.  formed  in  the  presence  of 
excess  water  would  differ  from  that  formed  in  the  presence  of  excess  oil. 
The  percentage  composition  in  each  case  appears  to  be  the  same. 

F.  G.  COTTRELL,  Washington,  D.  C. — In  electrical  demulsification 
experiments  in  the  West  a  number  of  years  ago,  we  found  no  lower  limit 
to  the  size  of  globules  in  an  emulsion  that  could  be  dealt  with,  and  I 
believe  this  has  been  borne  out  in  the  operation  of  the  commercial  plants 
that  grew  out  of  this  work  and  are  in  operation  today.     I  am  therefore 
surprised  at  the  results  that  Mr.  Trager  has  secured,  and  am  inclined  to 
think  that  he  may  not  have  applied  the  treatment  in  the  same  way, 
because  it  was  with  those  very  fine  emulsions  that  we  were  working  in  our 
experiments. 

E.  A.  TRAGER. — The  chemical  laboratory  worked  on  this  same  sub- 
ject and  tried  using  a  high  voltage  current  to  break  down  the  emulsion, 
but  the  results  were  not  commercially  practical  for  it  was  found  necessary 
to  treat  fine  emulsions  several  times  before  they  were  completely  broken 
down. 

F.  G.  COTTRELL. — Do  you  know  the  details  of  the  experiments — the 
voltages  and  conditions? 

CHAIRMAN  WASHBURNE. — I  believe  you  used  high  voltages  in  your 
experiments  did  you  not,  and  alternating  current? 

F.  G.  COTTRELL. — Yes. 

CHAIRMAN  WASHBURNE. — It  seems  to  me,  since  there  is  no  doubt  that 
every  globule  must  have  its  charge  of  static  electricity,  the  smaller  the 
globule,  the  easier  it  would  be  moved  by  electrical  currents  and  discharges. 
The  normal  static  charges  will  be  of  like  kind  and  proportional  to  the 
surface  area  of  the  globules  of  oil  which  will  vary  with  the  square  of  the 
radius,  while  the  volume  to  be  moved  will  be  proportional  to  the  cube  of 
the  radius.  It  is  very  evident,  from  the  consideration  of  squares  versus 


456  INVESTIGATIONS   CONCERNING   OIL-WATER   EMULSION 

cubes,  that  it  must  be  easier  to  combine  large  drops  than  small  ones, 
because  the  smaller  they  are,  the  easier  it  is  for  these  little  static  charges 
to  keep  the  globules  from  quite  touching  each  other.  These  are  all 
technical  questions  and  of  value  in  the  manipulation  of  oil  emulsions. 
In  the  geological  sense,  there  can  be  no  emulsion.  In  unlimited  time, 
the  globules  must  come  together  and  coalesce  into  larger  bodies,  thereby 
destroying  the  emulsion. 

E.  A.  TRACER. — I  had  a  discussion  with  Dr.  Born  (chief  chemist) 
on  the  subject  of  electrical  treatment  of  emulsions  and  the  folio  whig  are 
the  conclusions  arrived  at:    The  smaller  bubbles,  as  Mr.  Washburne 
says,  move  toward  the  electrode  with  greater  speed,  and  when  two  such 
bubbles  collide  or  when  these  small  bubbles  strike  the  electrode,  the 
tendency  is  rather  to  break  down  into  even  smaller  bubbles  than  to 
coalesce.     The  larger  bubbles  apparently  move  more  slowly  and  when 
two  meet  they  coalesce  quite  readily. 

F.  G.  COTTRELL. — There  are  two  entirely  distinct  technical  processes 
which  are  often  confused  with  one  another.     One  is  the  electrical  pre- 
cipitation of  suspended  particles  out  of  a  gas  with  a  direct  or  at  least 
unidirectional  current,  and  the  other  is  the  demulsification  of  liquid 
mixtures  using  an  alternating  current.    The  fundamental  phenomena  on 
which  these  are  based  are  quite  different  as  they  are  actually  carried  out. 

In  the  first  case,  the  suspended  particle  takes  a  charge  by  convection 
from  one  electrode,  and  then  is  driven  over  and  deposited  on  the  other 
electrode.  In  the  case  of  the  demulsification  of  the  oil  and  water  mix- 
tures with  the  alternating  current,  however,  there  is  no  steady  migration 
toward  either  electrode.  The  field  is  continually  reversing  so  the  only 
tendency  is  for  the  irregularly  distributed  globules  of  water  to  arrange 
themselves  along  the  shortest  lines  between  the  electrodes.  With  a  very 
fine  emulsion,  you  may  easily  observe  this  through  a  microscope,  the 
globules  forming  chains  and  gradually  coalescing  along  these  chains.  In 
all  probability,  the  apparent  contact  is  not  directly  between  the  actual 
oil  in  the  globules  but  is  a  contact  of  a  film  of  impurities  projected  to  the 
surface  of  the  globules.  With  perfectly  pure  paraffin-oil  and  water,  it  is 
very  difficult,  if  not  impossible,  to  make  a  reasonably  permanent  emulsion, 
but  by  adding  a  trace  of  some  resin  or  similar  substance  to  the  oil,  the 
emulsion  becomes  stable  at  once.  In  crude  oils  there  are  varying 
amounts  of  such  material.  Large  drops  tend  to  flow  together  and  break 
through  that  film  by  the  force  of  gravity.  As  the  size  of  the  globules 
decreases,  a  limit  is  reached  where  that  force  is  no  longer  sufficient  to 
press  the  globules  together  sufficiently  to  break  through  these  films,  but 
if  the  globules  are  polarized  by  being  brought  between  the  electrodes, 
it  may  be  possible  to  puncture  that  film  enough  to  make  them  coalesce. 
That  is  the  picture  of  the  process  I  have  formed  from  watching  it  under 


DISCUSSION  457 

the  microscope  and  from  the  general  action  I  have  seen  in  the  electric 
treaters.  In  the  case  of  the  demulsifying  process,  it  is  not  a  matter  of 
electricity  being  actually  discharged  from  one  electrode  to  the  globule, 
but  of  the  water  being  a  better  conductor,  and  of  the  consequent  tendency 
for  water  bubbles  to  arrange  themselves  in  the  oil  along  the  shortest  lines 
between  the  electrodes.  This  finally  brings  the  globules  into  contact  and 
causes  their  coalescence. 

R.  W.  MOORE. — Did  you  use  distilled  water,  and  what  type  of  oil? 

E.  A.  TRAGEB. — In  these  experiments  we  used  ordinary  city  water 
which  comes  from  the  river  and  contains  considerable  inorganic  matter. 
The  oil  was  Augusta  crude. 

R.  W.  MOORE. — Were  any  chemical  means  taken  to  bring  down  the 
emulsion,  such  as  treating  the  emulsion  with  salts? 

E.  A.  TRAGER. — We  found  nothing  that  would  treat  all  types  of 
emulsion  and  do  it  economically. 

CHAIRMAN  WASHBURNE. — Were  any  of  these  experiments  repeated 
with  different  oils?  Sometimes  one  emulsified  oil  will  act  very  differently 
from  another,  although  both  come  from  the  same  field. 

E.  A.  TRACER. — We  used  oil  from  eight  or  ten  wells,  but  all  the  wells 
were  in  Kansas. 

CHAIRMAN  WASHBURNE. — Can  you  tell  us  anything  about  the 
chemical  means  of  separating  emulsions? 

E.  A.  TRAGER. — I  believe  a  process  is  now  being  used  in  Oklahoma 
that  employs  sodium  salts  and  various  other  compounds  (preparations 
similar  to  soft  soap),  but  I  do  not  know  whether  or  not  they  are  com- 
mercially successful. 

R.  W.  MOORE. — Where  the  oil  is  emulsified  in  the  water,  heat  under 
pressure  was  worked  out  very  nicely  in  some  of  the  European  products, 
particularly  in  lubricating  oil.  There  is  a  very  rapid  separation,  so,  if  a 
man  is  treating  lubricating  oil  under  a  heavy  pressure,  he  can  throw  that 
in  his  tanks  and  get  a  very  rapid  separation  by  purely,  we  may  say, 
mechanical  and  not  chemical  means. 

CHAIRMAN  WASHBURNE. — Is  pressure  an  essential  part  in  that 
operation? 

R.  W.  MOORE. — I  do  not  know.  It  is  claimed  that  under  ordinary 
conditions  of  heating  they  got  no  separation  but  with  the  oil  and  water 
emulsion  under  about  60  Ib.  pressure  they  did. 


458  INVESTIGATIONS   CONCERNING   OIL-WATER   EMULSION 

R.  E.  COLLOM,*  Washington,  D.  C.  (written  discussion).  —  The  writer 
disagrees  with  the  definition  and  use  of  certain  terms  in  the  paper.  The 
second  paragraph  says:  "  Laboratory  investigations  were  conducted  in 
an  attempt  to  learn  the  composition  and  some  of  the  properties  of  emulsi- 
fied oil,  or  B.  S.,  as  it  is  more  commonly  called.  ...  In  this  discussion 
we  will  limit  the  term  B.  S.  to  that  heavy,  dark-brown  emulsion  com- 
posed of  a  physical  mixture  of  water,  oil,  and  air  with  some  included  inert 
matter,  either  organic  or  inorganic." 

The  abbreviation  B.  S.,  in  oil-field  practice,  is  never  properly  applied 
to  an  emulsion.  B.  S.  may  contain  some  emulsion  in  the  form  of  sludge, 
which  is  a  mixture  of  mud  —  derived  from  clay  or  shale  —  and  emulsified 
fluid.  But  B.  S.  means  "bottom  sediments"  or  "  bottom  settlings"  and 
such  sediments  are  entirely  different  and  distinct  from  oil-water  emulsions. 
Bottom  sediments  contain  certain  definite  ingredients  of  oil-well  produc- 
tion that  have  no  commercial  value.  They  include  sand,  mud,  sludge, 
and  other  semisolid  material.  Oil-well  emulsions,  when  properly  treated 
by  electric  dehydrators  or  other  means,  give  up  certain  quantities  of 
valuable  oil.  The  term  B.  S.  certainly  excludes  the  greater  bulk  of  emul- 
sions, which  are  nothing  more  or  less  than  mechanical  mixtures  of  oil  and 
water.  The  writer  prefers  the  use  of  the  word  "sludge,  "  rather  than  the 
abbreviation  B.  S.,  for  the  particular  physical  mixture  —  in  bottom  sedi- 
ments —  containing  emulsion. 

Emulsified  fluids  vary  in  their  combined  proportions  of  oil  and  water. 
The  gravities  of  the  oil  undoubtedly  control  the  proportion  of  oil  and 
water  in  emulsified  mixtures.  Light  oil  will  carry  less  free  water  in  sus- 
pension than  heavy  oil  but  an  emulsion  of  light  oil  and  water  will  show  a 
higher  water  content  than  one  of  heavy  oil  and  water.  If  the  Baume" 
gravity  of  the  pure  oil  in  emulsion  is  known,  a  fairly  close  figure  for  the 
percentage  of  water  in  the  emulsion  may  be  determined  in  the  following 
manner.  Baume*  gravities  are  proportional  to  volumes.  The  Baume* 
gravity  of  water  is  10.  The  Baume"  gravity  of  each  fluid,  multiplied  by 
the  respective  percentage  of  volume  of  each  fluid  and  divided  by  the  sum 
of  percentages  of  volume,  or  1,  equals  the  Baume"  gravity  of  the  emulsion. 
That  is,  where 

p   =  gravity  of  pure  oil; 

w  =  gravity  of  water; 

e    =  gravity  of  emulsion; 

x    =  per  cent  volume  of  pure  oil  ; 

y    =  per  cent  volume  of  water; 

-.        x  +  y  =  1.0        x-l-y 


P    —  py  +  wy  =  e  p  —  y  (p  —  w)  =  e 

6,  p,  and  w  are  known,  solve  for  y. 


Petroleum  Technologist,  U.  S.  Bureau  of  Mines. 


DRILLING   AND   PRODUCTION  TECHNIQUE   IN  THE  BAKU   OIL   FIELDS      459 


Drilling  and  Production  Technique  in  the  Baku  Oil  Fields 

BY  ARTHUR  KNAPP,  M.  E.,  SHREVEPORT,  LA. 

(New  York  Meeting,  February,  1920) 

No  OIL  territory  in  the  world  has  been  so  rich  in  large  producing  wells, 
in  a  comparatively  small  area,  as  the  Baku  field.  Particularly  is  this 
true  of  the  Bibi  Eibat  field,  which  formerly  produced  millions  of  "  poods  " 
of  "  gusher,"  or  as  it  is  called  in  Russia,  "  fountain  "  oil.  The  Bibi  Eibat 
and  Balachany  fields  have  been  exhausted  of  gas  and  ruined  by  water,  but 
the  Surachany  and  Benegadi  fields  are  still  fountain  territories  and  many 
outlying  districts  that  have  only  been  prospected  produce  rich  fountains. 

The  method  of  controlling  fountains,  or  gushers,  is  the  result  of  growth, 
along  with  the  Russian  system  of  drilling,  where  large  diameters  and 
riveted  casing  have  been  in  vogue.  The  screw  casing  is  seldom  used 
except  to  exclude  water.  Formerly  the  method  of  finishing  wells  and 
the  condition  of  the  casing  at  the  top  of  the  well  would  not  permit 
the  use  of  gates,  manifolds,  and  connections  as  is  standard  elsewhere. 

The  life  of  the  flowing  wells  is  very  short,  particularly  those  10  in. 
(25  cm.)  or  more  in  diameter,  which  produce  large  quantities  of  sand  and 
often  flow  for  but  a  few  days  and  are  then  a  complete  loss.  More  than 
1,000,000  poods  in  24  hr.  have  been  claimed  in  several  instances,  but  in 
no  case  was  the  flow  for  more  than  a  few  days. 

The  oil  sands  of  this  district  are  free  uncemented  sands  and  vary 
in  thickness  from  paper  thin  to  a  maximum  of  10  ft.  (3  m.).  The  sands 
are  interlaid  with  strata  of  soft  clay.  In  spite  of  this,  the  practice  has 
been  to  drill  into  such  sands  and  produce  from  the  open  hole  without 
screen  or  liners.  Sometimes  the  casing  is  set  below  the  oil  sand  but  in 
this  case  holes  from  2J^  to  3  in.  in  diameter  are  drilled  opposite  the  oil 
sand,  which  would  not  have  the  effect  of  a  screen. 

Fig.  1  is  an  outline  of  the  fountain  shield  ready  for  the  control  of  a 
fountain.  It  is  composed  of  an  inner  and  an  outer  covering  made  from 
rough  boards.  The  framework  is  made  of  rough  round  poles.  When 
a  light  flow  is  expected,  only  the  inner  lining  is  built;  and  when  the 
fountain  comes  in  unexpectedly,  it  is  often  possible  to  build  only  the 
outer  cover.  The  bridge  is  for  the  purpose  of  renewing  the  blocks  as 
they  become  worn  by  the  flow.  The  lower  block,  as  here  shown,  is 
made  of  hardwood  and  is  bolted  to  the  crossbeams  with  brass  bolts. 
The  grain  end  is  toward  the  flow.  The  upper  block,  as  shown  here, 
is  made  of  cast  steel  and  is  also  bolted  to  the  crossbeam  with  brass  bolts. 


460      DRILLING  AND  PRODUCTION  TECHNIQUE  IN  THE  BAKU  OIL  FIELDS 


Sand  Sheave 
Crown  Block 


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Fio   2. 


ARTHUE   KNAPP 


461 


Both  blocks  may  be  wood  or  steel,  depending  on  the  fancy  of  the  engi- 
neer in  charge. 

Valves,  tees,  and  lead  lines  are  sometimes  put  on  the  well  to  prevent 
its  flowing  before  the  shield  is  complete  and  to  control  the  well  in  case 
of  fire.  No  attempt  is  made  to  control  the  production  or  to  direct  the 
flow  when  the  well  is  put  to  producing;  the  well  is  always  allowed  to 
flow  to  capacity  against  the  blocks.  Usually  the  valves  are  cut  out 


FIG.  3. — INTERIOR  OF  DERRICK  SHOWING  END  OF  WALKING  BEAM  AND  TEMPER-SCREW 


and  rendered  useless  soon  after  the  flow  commences.  The  wear  of  the 
blocks  depends  on  the  flow;  sometimes  they  must  be  renewed  daily. 
This  arrangement  of  fountain  control  is  not  always  effective.  The  top 
of  the  derrick,  blocks  and  all,  is  sometimes  lifted  entirely  off  and  the  well 
flows  wild  until  it  sands  up  or  the  flow  has  weakened  sufficiently  to  allow 
the  blocks  to  be  replaced.  The  derricks  are  usually  set  on  embank- 
ments from  6  to  10  ft.  high,  these  embankments  being  reinforced  with 
pilings  lined  with  planks.  This  bank  is  necessary  to  allow  the  oil  to  flow 


462      DRILLING  AND  PRODUCTION  TECHNIQUE  IN  THE  BAKU  OIL  FIELDS 

away  from  the  well  and  to  give  space  for  the  handling  of  the  large 
amount  of  sand  that  some  of  the  wells  produce. 

Fig.  2  is  an  exact  copy  of  the  record  of  six  wells  in  the  Balachany  field. 
It  shows  the  average  condition  of  producing  wells  drilled  by  the  Russian 
method.  In  general,  the  formation  to  1100  ft.  (335  m.)  is  clay,  shale,  and 
sandy  shale.  Below  1100  ft.,  there  is  also  soft  limestone,  soft  sandstone, 
and  hard  shale.  There  are  no  thick  layers  of  hard  rock.  Sand,  entirely 
uncemented,  is  seldom  found  except  in  thin  layers  between  layers  of 
shale. 


FIG  4. — WELL  BLOWING  OUT  THROUGH  26-iN.  CASING.     MAKING  GAS, 

WATER  AND  LARGE  QUANTITIES  OF  SAND. 


The  Russian  riveted  casing  is  far  from  water-tight,  which  accounts 
for  the  large  amount  of  cement  put  in  around  the  casing.  Sometimes  it  is 
necessary  to  fill  the  casing  with  clay  before  the  liquid  cement  will  remain 
behind  the  casing  long  enough  to  set.  The  cement  is  put  in  with  pumps, 
1  or  IJ^-in.  (2.5  or  3.8-cm.)  pipes  being  inserted  between  the  casings  to 
convey  it  to  its  place. 

The  Russian  method  of  drilling  makes  use  of  steel  poles  to  actuate 
the  tools  but  differs  from  the  Canadian  system,  which  also  uses  poles  of 
wood  or  iron,  in  that  a  "free-fall"  is  used  above  the  tools  instead  of  the 


ARTHUR   KNAPP  463 

tools  dropping  with  the  rods.  This  free-fall  picks  up  the  tools  at  the 
bottom  of  the  stroke  and  releases  them  at  the  top  of  the  stroke,  allowing 
them  to  fall  free  to  the  bottom  of  the  hole.  Thus  the  fall  is  limited  to 
the  length  of  the  stroke  of  the  walking  beam  and  differs  from  the  American 
cable  tool  system  where  the  fall,  due  to  the  elasticity  of  the  drilling  cable, 
may  be  several  times  the  stroke  of  the  beam. 

The  Russian  drilling  machine  is  a  slow  ponderous  machine,  very 
heavy  and  very  hard  to  handle,  transport,  and  install.  It  cannot  be 
said  in  reality  that  this  machine  drills;  it  manages  to  worry  a  hole  in  the 
ground.  The  results,  as  shown  in  the  tables,  prove  this.  The  large 
starting  diameters  are  necessary  because  of  the  large  number  of  strings 


FIG.  5. — TYPICAL  VIEW  IN  BALACHANY. 

of  casing  used  and  the  large  oil  string  necessary  for  producing  by  bailing. 
Also,  there  are  several  producing  horizons,  and  wells  are  drilled  large 
into  the  first  horizon  so  that  later  they  may  be  deepened.  Casing, 
both  Russian  riveted  and  screwed,  is  lowered  by  means  of  clamps  some- 
what on  the  style  of  the  American  casing  clamp.  The  Russians  have 
never  developed  nor  learned  to  use  elevators,  spiders  and  slips,  casing 
tongs,  or  other  modern  oil-well  tools,  except  when  these  tools  have  been 
brought  in  with  American  machinery  and  used  by  the  American  drillers. 
The  casing  is  always  carried  with  the  tools  in  the  Russian  system. 
The  bit  is  seldom  advanced  more  than  20  ft.  (6  m.)  beyond  the  shoe. 
Under-reaming  is  practised  to  a  large  extent. 

Tables  1  and  2  are  chronological  records  of  two  wells  shown  in  Fig.  2. 
They  give,  in  detail,  the  time  required  for  various  operations  under 
ordinary  circumstances.  When  one  string  of  casing  has  been  carried 


464      DRILLING  AND  PRODUCTION  TECHNIQUE  IN  THE  BAKU  OIL  FIELDS 

TABLE  1. — Casing  Record  Shown  in  Well  5,  Fig.  2 


Days 

Depth, 
Feei 

Advance, 
Feet 

Average 
•pei  Day, 
Feet 

Diameter 
of  Casing, 
Inches 

Operation 

10 

133 

133 

13 

42 

Drilling. 

2 

Lowering  36-in.  casing,  64  ft.  per  day. 

6 

230 

87 

15 

36 

Drilling. 

2 

Shut  down,  no  boiler  water. 

2 

260 

30 

15 

36 

Drilling. 

10 

Shut  down,  no  boiler  water. 

5 

370 

110 

22 

36 

Drilling, 

8 

Shut  down,  no  boiler  water. 

10 

585 

215 

21 

36 

Drilling. 

2 

Shut  down,  no  boiler  water. 

6 

714 

129 

21 

36 

Drilling. 

8 

Lowering  34-in.  casing,  90  ft.  per  day. 

17 

1000 

286 

17 

34 

Drilling. 

11 

Lowering  32-in.  casing,  90  ft.  per  day. 

19 

1250 

250 

15 

32 

Drilling. 

7 

Working  casing. 

6 

Lowering  26-in.  casing,  210ft.  per  day 

80 

Cementing. 

9 

Lowering  20-in.  casing,  135  ft.  per 

day. 

13 

1315 

65 

5 

20 

Drilling. 

6 

Taking  out  20-in.  riveted  casing,  220 

ft.  per  day. 

13 

Lowering  20  in.  screwed  pipe,  100  ft. 

per  day 

143 

Cementing. 

11 

Lowering  18-in.  casing,  120  ft.  per 

day. 

2 

1336 

21 

10 

18 

Drilling. 

6 

Shut  down  for  repairs. 

11 

1449 

113 

10 

18 

Drilling. 

10 

Testing  casing. 

75 

Cutting   off  18-in.,  lowering  16-in., 

and  cementing. 

27 

1687 

238 

9 

16 

Drilling. 

165 

Lowering  10-in.  casing  and  cement- 

ing. 

30 

Waiting  for  cement  to  set. 

60 

Bringing  well  in. 

Days  of  work,  730;  days  drilling,  128  or  18.2  per  cent.;  days  lowering  casing,  98  or 
14.0  per  cent. ;  days  idle,  28  or  0.4  per  cent.  Average  advance  per  day  of  actual  drilling 
13.2  ft.  Days  of  work  do  not  include  the  last  60  days  testing  for  oil  and  bringing  the 
well  in. 


ABTHUB  KNAPP 


465 


TABLE  2. — Casing  Record  Shown  in  Well  6,  Fig.  2 


Days 

Depth, 
Feet 

Advance, 
Feet 

Average 
per  Day 
Feet 

Diameter 
of  Casing 
Inches 

Operation 

16 

136 

136 

8 

42 

Drilling 

4 

Lowering  36-in.  casing,  34  ft.  per  day. 

2 

150 

14 

7 

36 

Drilling. 

1 

Testing  well  for  plumbness. 

5 

246 

96 

19 

36 

Drilling. 

3 

Machinery  repairs. 

6 

373 

127 

21 

36 

Drilling. 

1 

Machinery  repairs. 

20 

735 

362 

18 

36 

Drilling. 

14 

Lowering  34-in.  casing,  29  ft.  per  day. 

20 

987 

252 

12 

34 

Drilling. 

6 

Waiting  for  material. 

9 

Lowering  28-in.  casing,  102  ft.  per  day. 

19 

1166 

179 

9 

28 

Drilling. 

23 

Cementing. 

10 

Lowering  26-in.  casing,  116  ft.  per  day. 

23 

1340 

134 

6 

26 

Drilling. 

19 

Working  casing. 

8 

Lowering  24-in.  casing,  166  ft.  per  day. 

6 

No  steam. 

9 

1393 

53 

6 

24 

Drilling. 

14 

Working  casing,  etc. 

9 

Lowering  22-in.  casing,  154  ft.  per  day. 

5 

1414 

21 

4 

22 

Drilling. 

52 

Working  casing,  etc. 

10 

Lowering  20-in.  casing,  154  ft.  per  day. 

27 

1484 

70 

2M 

20 

Drilling,  also  working  casing. 

19 

1575 

91 

5 

20 

Drilling. 

8 

Working  casing,  etc. 

12 

Lowering  18-in.  casing,  146  ft.  per  day. 

13 

1676 

101 

8 

18 

Drilling. 

39 

Freeing  and  repairing  casing. 

14 

1701 

25 

2 

18 

Drilling. 

17 

Freeing  and  repairing  casing. 

95 

Lowering  16-in.  screwed  casing,  wait- 

ing orders. 

25 

1911 

210 

8 

16 

Drilling. 

12 

Working  casing. 

27 

Lowering  14-in.  screwed  casing,  71  ft. 

per  day. 

4 

General  repairs. 

5 

1946 

35 

7 

14 

Drilling. 

12 

i 

Shut  down,  labor  troubles. 

14 

2044 

98 

7 

14 

Drilling. 

8  months  waiting  result  of  an  offset  well 


15 

Lowering  12-in.  screwed    casing,    130 

ft.  per  day. 

9 

Repairs. 

26 

2184 

140 

5M 

14 

Drilling. 

Days  of  work,  737;  days  drilling,  268  or  36.3  per  cent.;  days  lowering  casing,  130 
or  17.5  per  cent.;  days  idle,  29  or  0.4  per  cent.    Average  advance  per  day  of  actual 
drilling  8.15  ft.    Average  amount  of  casing  lowered  per  day,  140  ft. 
VOL.  LXV,— 30. 


466      DRILLING  AND  PRODUCTION  TECHNIQUE  IN  THE  BAKU  OIL  FIELDS 

as  far  as  possible,  a  smaller  string  must  be  lowered  before  drilling  can 
be  continued.  The  time  required  for  this  is  a  large  item  and  appears  in 
detail  in  the  column  marked  Operations.  The  general  character  of  the 
Russian  method  accounts  for  most  of  the  slow  progress,  together  with 
poor  tools,  material,  and  labor.  Wells  are  usually  drilled  by  contractors 
who  are  paid  per  linear  foot  on  a  sliding  scale,  depending  on  the  depth. 
They  are  paid  a  fixed  sum  per  day  while  fishing  and  are  not  liable  for 
casing  lost. 

Days  of  work  does  not  include  the  8  months  waiting  on  the  result 
of  another  well.  Working  casing  includes  cementing,  testing  for  water, 
raising  and  lowering  casing  to  free  it,  cutting  off,  etc.  Days  drilling 
includes  time  of  raising  and  lowering  tools  and  the  lowering  of  casing 
as  the  drilling  proceeds. 

DISCUSSION 

I.  N.  KNAPP,  Philadelphia,  Pa.  (written  discussion). — I  had  con- 
siderable correspondence  with  the  author  of  this  paper  during  the  two 
years  he  was  engaged  at  Baku,  from  July,  1914,  to  August,  1916,  and 
since  his  return  I  have  had  many  interesting  talks  with  him  on  his  Rus- 
sian experience.  I  think,  therefore,  that  instead  of  making  a  strictly 
technical  discussion  of  the  paper,  it  will  be  more  interesting  to  include 
some  personal  details. 

The  author  was  employed  to  advise  on  American  methods  of  drilling 
and  operating  and  particularly  to  introduce  American  methods  of  pump- 
ing oil  from  wells.  Fully  one-third  of  the  oil  then  being  produced  around 
Baku  was  used  as  fuel  for  bailing  the  production. 

On  arriving  at  his  destination  he  was  not  allowed  by  the  local  Russian 
management  to  go  upon  the  properties  of  the  company  that  had  em- 
ployed him.  This  gave  him  an  opportunity  to  study  the  Russian  lan- 
guage under  competent  teachers;  in  6  mo.  he  was  able  to  do  business 
over  the  telephone  in  that  language.  In  talking  of  this  I  said  "It  was 
extremely  fortunate  that  you  were  able  to  learn  Russian  in  such  a  way 
that  you  did  not  have  to  differentiate  the  common  '  cuss  words '  of  the  oil 
fields  from  polite  language."  To  this  he  replied  that  Russian  is  not 
commonly  spoken  by  the  workmen  of  the  Baku  oil  fields.  The  principal 
language  used  is  Tartaric  with  a  mixture  of  Persian,  Armenian,  and  some 
Georgian. 

After  several  months  of  idleness,  he  was  given  a  practically  abandoned 
well  to  put  to  pumping.  The  Russian  manager  seemed  to  expect  him 
to  tear  down  the  Russian  rig  and  build  one  in  American  fashion,  which 
could  easily  be  made  to  take  a  year's  time.  He  chose  rather  to  repair  and 
line  up  the  old  Russian  rig  and  machine  already  at  the  well  and  on  running 
the  tools  found  a  couple  of  bailers  stuck  in  the  hole.  The  workmen 
were  surprised  to  see  an  American  engineer  who  was  not  afraid  to  repair 


DISCUSSION  467 

one  of  their  machines  and  operate  it.  The  author  soon  found  that  some 
of  the  workmen  were  good  oil  men  in  their  way,  so  after  he  had  run  an 
impression  block,  had  some  fishing  tools  shaped  up,  and  had  cleared  the 
junk  out  of  the  hole,  they  became  willing  and  helpful  workers.  He  found 
blacksmiths  and  machinists  in  the  field  that  could  do  surprisingly  good 
work,  considering  the  facilities  they  had.  The  workmen  had  never  used 
American  elevators,  modern  pipe  tongs,  monkey  or  Stillson  wrenches,  so 
it  was  necessary  to  show  them  how  to  use  such  tools  efficiently.  The 
several  large  properties  of  his  company  had  no  tools  of  this  kind  until 
the  shipment  of  American  goods  arrived. 

The  first  well  was  soon  got  on  the  beam  and  put  to  pumping.  The 
author  assures  me  that  there  is  no  more  difficulty  in  pumping  a  properly 
screened  well  from  the  Baku  sands  than  from  the  Midway,  Calif.,  sands 
where  he  has  had  experience  in  both  drilling  for  and  pumping  oil.  Also, 
he  says  that  many  places  in  Louisiana  and  in  Trinidad  present  greatei 
difficulties  in  drilling  and  pumping  than  Baku. 

A  second  practically  abandoned  well  was  turned  over  to  him  to  be  put 
to  pumping  but  instead  of  the  good  American  tubing  got  for  the  purpose 
a  lot  of  junk  tubing  that  would  drop  apart  before  1000  ft.  was  run  in 
the  hole  was  substituted.  Each  break  made  a  fishing  job  that  would  last 
some  time.  After  awhile  the  Russian  management  forgot  about  trying 
to  pump  wells. 

The  author  was  given  an  opportunity  to  become  familiar  with  the 
Russian  free-fall  system  of  drilling  and,  for  a  time,  had  charge  of  the 
operation  of  a  Holland  rig,  or  European  water-flush  system,  and  an 
American  rotary.  He  understood  that  it  was  compulsory  for  each  oil 
property  to  be  managed  by  a  qualified  engineer  with  Russian  diplomas 
and  such  managers  commonly  opposed  any  innovations  on  general 
principles. 

In  some  of  the  Government-owned  pools,  operations  are  restricted  to 
hand-dug  wells  not  to  exceed  a  maximum  depth  of  420  ft.  The  well 
diggers  employed  are  skilled  in  their  trade,  which  has  been  carried  on  in 
that  region  since  time  immemorial.  They  are  very  loyal  to  their  mates. 
Men,  when  digging,  are  frequently  overcome  with  gas  and  the  workmen 
are  adepts  at  resuscitation  in  such  cases.  The  laws  of  the  country  have 
been  made  extremely  drastic  on  deaths  caused  by  asphyxiation.  When 
the  workers  conclude  that  a  man  is  really  dead  from  this  cause,  they 
pound  him  on  the  head  with  a  rock  or  kick  in  his  ribs  so  as  to  claim  that 
he  died  from  an  accident  and,  of  course,  the  authorities  decide  in  such 
cases  that  nobody  is  to  blame. 

He  further  said  that  the  rules  laid  down  for  operations  in  the  Baku 
field  were  perhaps  made  in  good  faith  but  many  lacked  practicability. 
For  instance,  there  was  a  rule  that  only  60  Ib.  of  steam  was  to  be  allowed 
ordinarily  on  any  boiler  in  the  field.  American  rotary  rigs  are  designed 


468      DRILLING  AND  PRODUCTION  TECHNIQUE  IN  THE  BAKU  OIL  FIELDS 

for  at  least  100  Ib.  steam  pressure  and  were  hard  to  operate  at  the  low 
pressure  on  account  of  the  small  steam  cylinders.  Some  boilers  sent 
with  such  rigs  were  built  under  the  Burmah  specification  and  really  had  a 
fair  factor  of  safety  at  200  Ib.  steam  pressure.  But  notwithstanding 
all  this  every  boiler  in  the  field  must  have  two  safety  valves,  one  of  which 
is  set  at  60  Ib.  pressure  and  sealed  by  a  Government  engineer.  Admit- 
tedly the  water  used  is  bad  but  not  the  slightest  regard  is  paid  to  the 
thickness  of  the  sheets  or  the  workmanship  of  the  boiler.  Gradually 
the  author  was  permitted  to  examine  all  the  geological  and  drilling 
records  of  his  company  from  which  the  data  given  in  the  paper  were  taken. 

There  were  a  few  native  Russians  in  the  Baku  district  who  had  studied 
in  American  and  English  colleges  and  occasionally  one  was  employed 
in  the  oil  fields.  Partly  through  the  influence  of  these  men  and  partly 
because  of  his  ability  to  speak  Russian  fluently  and  to  make  sketches  of 
American  methods  of  drilling  and  operating  he  was  invited,  during  the 
last  few  months  of  his  stay  at  Baku,  to  attend  and  take  part  in  the  pro- 
ceedings of  the  weekly  meetings  held  by  the  Government  engineers  in 
general  charge  of  the  Baku  oil  fields.  He  says  that  it  is  generally  recog- 
nized that  the  days  of  the  rich  shallow  gushers,  or  fountains,  at  Baku 
have  passed  and  less  expensive  methods  of  drilling  and  operating  must 
be  adopted,  such  as  is  offered  by  the  American  method  of  rotary  drilling, 
cementing  in  the  casing,  screening  off  the  sand,  and  pumping  the  wells. 

So  far  as  I  can  see,  the  first  great  step  toward  progress  would  be  to  do 
away  with  the  former  misdirected  Governmental  interference  of  all 
kinds.  Let  the  investigations  be  directed  by  men  skilled  in  the  oil 
business,  and  not  by  the  impractical  scientist  whose  findings  only  serve 
to  entrench  the  administrative  and  bureaucratic  machines  in  the  strangle 
hold  that  smothers  initiative,  progress,  and  real  conservation. 


DETERMINATION   OF   PORE   SPACE  469 


Determination  of  Pore  Space  of  Oil  and  Gas  Sands* 

BY  A.  F.  MELCHER,!  M.  S.,  WASHINGTON,  D.  C. 

(Lake  Superior  Meeting,  August,  1920) 

THE  present  paper  is  a  progress  report  on  an  investigation  of  the 
physical  factors  of  oil  and  gas  and  especially  of  their  sands,1  such  as  pore 
space,  size  of  pores  or  permeability,  retentivity,  viscosity  of  the  oil, 
temperature,  pressure,  thickness  and  area  of  the  pay  sand,  water  rela- 
tions, and  capillarity.  The  purpose  is  to  determine  as  many  of  these 
physical  factors  as  possible,  and  to  ascertain  the  relations  existing,  directly 
or  indirectly,  between  these  physical  factors  and  the  production  of  oil 
and  gas.  As  yet  only  pore  space2  and  size  of  grains  of  pay  sands  have 
been  investigated,  although  an  apparatus  has  been  designed  to  determine 
the  permeability  of  a  sand  to  oil,  water,  or  gas  under  definite  drops  of 
pressure  between  the  entrance  face  and  exit  face  of  the  sample. 

Messrs.  E.  W.  Shaw,  R.  Van  A.  Mills,  D.  Dale  Condit,  G.  B.  Richard- 
son, G.  C.  Matson,  and  C.  H.  Wegemann  collected  the  samples  upon 
which  the  physical  determinations  were  made.  Acknowledgment  is 
made  to  my  colleagues  of  the  United  States  Geological  Survey  for  many 
suggestions  and  criticisms;  to  Mr.  Mills  for  the  production  data  given 
of  the  oil  wells  from  which  some  of  the  samples  were  collected;  to  Mr. 
A.  W.  McCoy  of  the  Empire  Gas  and  Fuel  Co.,  Bartlesville,  Okla.,  for 
many  ideas. 

DETERMINING  PORE  SPACE  OF  OIL  AND  GAS  SANDS 

In  selecting  a  method  for  the  determination  of  pore  space,  two  objects 
were  kept  in  mind:  First,  the  method  must  not  only  be  sufficiently 


*  Published  by  permission  of  the  Director,  U.  S.  Geological  Survey. 
t  Associate  Physical  Geologist,  U.  S.  Geological  Survey. 

1  Sand  is  used  in  this  paper  with  the  meaning  of  oil  and  gas  pay  sands  as  they 
exist  in  nature,  either  coherent  or  incoherent.     The  sand  samples  tested  in  this  paper 
were  coherent. 

2  The  pore  space  of  a  rock  can  be  divided  into  two  kinds,  the  total  pore  space  and 
the  effective  pore  space.     The  total  pore  space  is  the  total  interstitial  space  and 
includes  not  only  the  communicating  pores,  but  any  isolated  pores  that  may  exist. 
The  effective  pore  space,  on  the  other  hand,  is  relative,  depending  on  such  factors  as 
the  constitution  of  the  liquid,  the  size  of  the  pores,  the  material  of  the  rock,  tem- 
perature, pressure,  and  other  conditions.     It  is  apparent  that  the  total  pore  space 
is  a  maximum  limit  for  the  effective  pore  space.     The  method  described  in  this  paper 
determines  the  total  pore  space. 


470  DETERMINATION   OF   PORE   SPACE 

accurate  to  be  of  a  truly  scientific  nature  but  must  also  be  rapid  enough 
to  justify  its  commercial  use.  Second,  the  method,  to  have  as  large  a 
range  as  possible,  must  permit  the  determination  of  pore  space  of  many 
types  of  samples  of  different  composition  and  structure,  with  great 
range  of  size.  The  method  selected  is  based  on  the  principle  that  the 
volume  of  the  fragment  of  the  sand  minus  the  volume  of  its  individual 
grains  equals  the  volume  of  the  pore  space.  The  volume  of  the  pore 
space  divided  by  the  volume  of  the  fragment  gives  the  per  cent,  pore 
space  by  volume.  The  volume  of  a  fragment  of  sand  is  chosen  because 
it  is  a  constant  factor.  Density  and  weight  of  a  fragment  of  sand  are 
not  constant  unless  all  substances  are  removed  from  its  pore  space,  but 
will  vary  with  the  quantity  and  kind  of  material  in  the  pores  of  the  stone. 
To  determine  the  pore  space  of  an  oil  or  gas  sand,  it  is  quite  necessary 
to  have  unbroken  fragments  or  parts  of  the  pay  sand  as  it  existed  in 
nature — free  from  cracks  or  cleavage  planes  and  its  surface  free  from 
foreign  material.  Disintegrated  sand  is  not  so  valuable  in  the  determina- 
tion of  pore  space,  as  it  would  be  impossible  to  place  the  separate  grains 
in  their  original  positions  in  order  that  their  true  interstitial  space 
might  be  found.  It  is  better  to  have  several  samples  from  each  well, 
beginning  at  the  top  of  the  pay  sand,  or  even  at  the  top  of  the  cap-rock 
and  extending  to  the  bottom  of  the  pay  sand,  as  often  the  productive 
sand  is  within  another  sand.  The  core-drill  method  of  obtaining  samples 
is  the  best.  Samples  are  obtained  when  the  well  is  shot  and  from  drill 
cuttings.  Sometimes  they  come  up  with  the  bailer  and  with  oil  and  gas 
when  oil  and  gas  come  out  of  the  well  under  considerable  pressure.  Sam- 
ples are  often  obtained  from  outcrops  and,  in  some  cases,  where  mine 
shafts  penetrate  the  pay  sand.  The  fragments  are  sometimes  irregular 
and  quite  small,  weighing  less  than  1  gram. 

DIPPING  SAMPLES  IN  PARAFFIN 

Sometimes  the  texture  of  the  samples  is  so  loose  that  it  is  difficult  to 
keep  the  grains  of  sand  from  rubbing  off  while  handling  them;  other  frag- 
ments are  firmer  and  more  compact.  It  was  because  of  this  looseness 
of  texture  and  the  small  size  of  some  of  the  samples  that  the  method  of 
dipping  in  paraffin3  was  adopted.  After  the  surface  of  a  sample  was 

•Julius  Hirschwald  ("Die  Priifung  der  Natiirlichen  Bausteine  auf  ihre  Wetter- 
bestandigkeit."  Berlin,  1908.  W.  Ernst  und  Sohn)  describes  a  method  of  dipping 
the  specimens  in  paraffin,  which  he  used  to  determine  the  specific  gravity  of  building 
stones.  The  volumenometer  was  employed  instead  of  weighing  the  sample  in  water 
to  find  the  specific  gravity.  He  determined  the  absolute  pore  space  from  a  compari- 
son of  the  specific  gravity  of  the  powdered  stone  with  that  of  a  greater  fragment 
of  the  stone.  By  the  method  of  finding  the  pore  space  by  a  comparison  of  specific 
gravities,  Hirschwald  eliminates  the  difficulties  of  saturating  the  sample  with  water, 
but  in  choosing  the  specific  gravity  instead  of  volume  he  retains  the  difficulties  of 
removing  foreign  material  from  the  pores  of  his  fragment  specimen. 


A.    F.    MELCHEK  471 

thoroughly  cleaned  of  foreign  material  with  an  assay  brush  and  loose 
particles  brushed  off,  it  was  broken  into  two  parts;  one  part  was  used 
for  finding  the  volume  of-the  fragment  and  the  other  was  used  for  finding 
the  volume  of  the  individual  grains  making  up  the  fragment. 

The  pieces  that  were  to  be  used  for  finding  the  volume  of  the  fragment 
were  weighed  and  then  dipped  into  parafiiin  heated  to  a  temperature  a 
little  above  its  melting  point.  The  layer  of  paraffin  around  the  sample 
was  then  examined  for  air  bubbles  and  pinholes.  If  any  were  found, 
they  were  removed  by  remelting  the  paraffin  at  that  point  with  the  end 
of  a  hot  wire. 


*  a 


FIG.  1. — SAMPLES  OF  OIL-  AND  GAS-BEABING  SANDS  DIPPED  IN  PARAFFIN;  THE  SCALE 

EEADS  IN  CENTIMETERS. 

The  fragments  are  best  dipped  by  holding  them  with  the  fingers. 
First,  the  half  of  the  sample  opposite  the  fingers  is  dipped,  then  the  sample 
is  turned  around  and  the  other  half  is  dipped.  The  samples  should  never 
remain  in  the  melted  paraffin  longer  than  2  or  3  sec.,  and  very  small  samples 
or  very  porous  ones  should  be  immersed  for  shorter  periods.  Bubbles 
should  not  be  permitted  to  come  out  of  the  samples  as  they  usually 
indicate  that  the  paraffin  is  beginning  to  enter  the  pores.  If  there  is  any 
doubt  about  the  paraffin  entering  the  pores  of  the  sample,  the  specimen 
may  be  broken,  after  it  is  weighed,  in  distilled  water  and  examined  with 


472  DETERMINATION   OF  PORE   SPACE 

a  hand  lens  or  microscope,  depending  on  the  size  of  the  pores.  It  will 
be  found  that,  after  a  little  practice,  if  the  samples  are  cold,  there  will 
not  be  much  difficulty  in  dipping  them  so  that  the  paraffin  will  not  enter 
the  pores,  as  the  paraffin  almost  immediately  hardens  when  it  comes  into 
contact  with  the  cold  surface  of  the  sand.  When  the  paraffin  cools, 
the  sample  with  its  coating  is  weighed  to  determine  the  weight  of  the 
paraffin. 

DETERMINING  VOLUME  OF  FRAGMENT 

The  sample  with  the  coating  of  paraffin  is  suspended  in  distilled 
water  by  a  No.  30  B.  &  S.  gage  platinum  wire  and  weighed;  a  fine  wire 
is  used  so  that  the  error  due  to  surface  tension  will  be  as  small  as  possible. 
The  water  should  have  been  boiled  and  its  temperature  taken  to  one- 
tenth  of  a  degree  at  the  time  of  the  weighing.  The  sample  is  then 
removed  from  the  water,  dried  by  pressing  the  surface  against  bibulous 
paper  or  a  smooth  towel  and  weighed  in  air.  This  weighing  is  made  to 
see  whether  the  sample  absorbed  any  water.  If  an  appreciable  quantity 
of  water  is  absorbed,  a  correction  can  be  made  to  the  weight  of  water 
displaced  from  the  difference  between  the  last  weighing  and  the  former 
weighing  of  the  sample  plus  the  paraffin  in  air. 

From  the  weight  of  the  water  displaced,  its  temperature,  and  den- 
sity, the  volume  of  the  sample  plus  the  volume  of  the  paraffin  can  be 
obtained.  The  tables  by  P.  Chappuis4  on  the  change  of  density  with  the 
temperature  of  pure  water  free  from  air  were  used.  From  a  previous 
determination  of  the  density  of  paraffin,  which  in  this  case  is  0.906,  and 
the  weight  of  the  paraffin  covering  the  sample,  its  volume  can  be  ob- 
tained. Subtracting  this  volume  from  the  total  volume  of  the  sample, 
plus  the  volume  of  the  paraffin,  gives  the  volume  of  the  fragment  of  stone 
used. 

DETERMINING  VOLUME  OF  INDIVIDUAL  GRAINS 

The  second  part  of  the  sample  is  weighed  and  crushed  in  an  agate 
crucible  into  its  separate  particles;  or,  in  the  case  of  a  very  fine  sand, 
until  it  will  pass  through  a  100-mesh  sieve.  It  is  again  weighed  and 
thoroughly  dried  in  an  electric  oven,  or  better  in  the  Steiger  toluene5 
bath  at  from  100°  to  150°  C.  for  30  min.  to  1  hr.;  a  lower  temperature 
is  used  when  there  is  danger  of  driving  off  an  appreciable  quantity  of 
combined  water.  It  is  then  placed  in  a  dessicator  to  cool.  After  the 
particles  have  cooled,  the  sample  is  weighed  and  exposed  to  the  air  to 
take  up  moisture.  After  the  particles  have  reached  a  constant  weight, 

4  Bureau  International  des  Poids  et  Mesures,  Travaux  et  Memoirs  (1907)   13; 
U.  S.  Bureau  of  Standards,  Circular  19,  5th  ed.,  Table  27. 
•  U.  S.  Geol.  Survey  Bull.  422  (1910)  75-76. 


A.    F.    MELCHER 


473 


or  nearly  so,  they  are  again  weighed  to  correct  for  hydroscopic  water. 
The  particles  of  sand  are  then  transferred  to  the  pycnometer,  using 
glazed  paper.  The  pycnometer  plus  the  sample  are  weighed  to  correct 
for  the  loss  in  transfer.  The  pycnometers  used  are  of  the  type  designed 
by  John  Johnston  and  L.  H.  Adams,6  of  the  Carnegie  Institution. 

The  advantages  of  this  type  of  pycnometer  over  others  are:  (1)  There 
is  no  appreciable  loss  by  evaporation  of  the  liquid  from  the  pycnometer, 
the  pycnometer  can,  therefore,  be  allowed  to  stand  in  the  balance  case 


FIG.  2. — APPARATUS  FOB  REMOVING  THE  AIR  FROM  DISINTEGRATED  SAND  IN 
PYCNOMETER,  AND  TWO  TYPES  OF  PYCNOMETERS,  THE  JOHNSTON  &  ADAMS  PLANE- 
JOINT  PYCNOMETERS,  No.  1,  AND  COMMON  PYCNOMETERS,  No.  2. 

until  temperature  and  moisture  equilibrium  is  attained;  (2)  there  is  no 
error  due  to  grease,  which  is  necessary  in  other  pycnometers  where  the 
stopper  fits  into  flask;  (3)  any  particle  of  grit  or  dirt  can  be  easily  wiped 
from  the  joint  between  the  stopper  and  flask.  It  is  about  as  easy  to 
obtain  an  accuracy  in  density  of  2  in  the  fourth  decimal  place  by  this 
pycnometer  as  it  is  of  2  in  the  third  decimal  place  for  the  ordinary  type 
of  pycnometer,  where  the  stopper  fits  inside  the  flask.  The  device  of  G. 

'Jnl  Amer.  Chem.  Soc.  (1912)  34,  566. 


474  DETERMINATION   OF   PORE    SPACE 

E.  Moore,7  slightly  modified  by  Day  and  Allen,8  was  used  for  the  evacua- 
tion of  the  air  from  the  ground  particles.  Fig.  2  shows  this  apparatus 
with  pycnometers  of  two  types — the  Johnston  &  Adams  plane  joint 
pycnometer  and  the  common  pycnometer,  in  which  the  stopper  fits  inside 
the  neck  of  the  flask. 

After  the  pycnometer  is  nearly  filled  with  boiled  distilled  water,  the 
aspirator  is  removed  and  the  pycnometer  is  placed  in  a  constant-tem- 
perature thermostat  regulated  to  0.1°  C.  The  filling  of  the  pycnometer 
is  completed  from  distilled  water  taken  from  another  vessel  in  the  thermo- 
stat. The  pycnometer  is  then  removed  from  the  thermostat  and  weighed 
after  its  outside  surface  has  been  dried  with  a  towel.  From  a  previous 
calibration  of  the  pycnometer,  which  gives  the  weight  of  the  water  nec- 
essary to  fill  the  pycnometer,  the  weight  of  water  that  the  crushed 
sample  displaced  is  found.  The  volume  of  the  ground  particles  in  the 
pycnometer  is  found  from  the  weight  of  water  displaced  and  the  table 
of  densities  of  water  at  the  temperature  of  the  thermostat. 

By  proportion,  the  total  volume  of  grains  in  the  fragment  dipped  in 
paraffin  is  determined.  Then  the  volume  of  the  fragment  dipped  in 
paraffin  minus  the  volume  of  its  grains  is  equal  to  the  volume  of  the  pore 
space.  This  volume  divided  by  the  volume  of  the  fragment  gives  the 
per  cent,  pore  space  by  volume. 

DETERMINING  PORE  SPACE  OF  VERY  SMALL  SAMPLES 

In  case  the  sample  is  too  small  to  break  into  two  parts,  the  whole 
sample  can  be  dipped  into  paraffin  and  the  paraffin  burned  off,  if  the 
grains  of  the  sample  are  of  sufficiently  pure  quartz  not  to  be  appreciably 
changed  in  volume  or  weight  by  the  burning.  In  many  cases  the  paraffin 
can  easily  be  shaved  and  brushed  off  with  a  knife  and  assay  brush  and 
a  new  weighing  made  to  determine  the.  loss  of  weight  of  particles  brushed 
off.  In  case  there  is  oil  in  the  fragment  that  is  crushed,  the  oil  is  either 
burned  out  by  placing  the  crushed  sample  in  a  platinum  crucible  or  it  is 
dissolved  by  a  solvent,  as  petroleum  ether  or  carbon  tetrachloride. 
It  was  possible  to  burn  out  the  oil  in  nearly  all  cases  as  most  of  the  samples 
consisted  of  practically  pure  quartz. 

BASIC  PRINCIPLE  OF  METHOD 

This  method  is  based  upon  the  principle  that  the  volume  of  the  frag- 
ment minus  the  volume  of  its  grains  equals  the  volume  of  the  pore  space. 
Let  V  =  volume  of  fragment; 

Vta=  volume  of  grains  of  that  fragment  free  from  moisture; 

Vp  —  volume  of  pore  space; 

v9  =  v  -  vto 0) 

» Am.  Jrd.  Sci.  [3]  (1872)  3,  41. 

•Carnegie  Institution  of  Washington  Pub.  31;  U.  S.  Geol.  Survey  Bull.  422 
(1910)  4&-50 


A.    F.    MELCHER  475 

The  per  cent,  pore  space  is 

~\T  \  ~\T  /  V    / 

Now,  the  problem  is  to  find  V  and  Vtg  in  known  quantities,  and  quan- 
tities that  can  easily  be  obtained  experimentally.  In  order  to  do  this, 
the  sample  is  broken  into  two  parts,  one  to  be  dipped  in  paraffin  and  the 
other  to  be  used  for  the  determination  of  the  volume  of  the  grains. 

Let  W  and  W\  =  weights,  respectively,  of  the  two  pieces; 

WP  =  weight  of  one  of  fragments  dipped  in  paraffin; 
Wp  —  W    =  weight  of  paraffin. 

The  volume  of  the  paraffin  is 

Vpl  =      0*906    ' 
wherein  0.906  =  density  of  paraffin  at  20.4°  C. 

Let  Wpi  =  weight  of  fragment  dipped  in  paraffin  plus  wire  carrier 

in  boiled  distilled  water; 

We  =  weight  of  wire  carrier  immersed  an  equal  distance  in 
water  as  when  fragment  was  attached. 

The  weight  of  the  water  displaced  by  the  fragment  plus  its'  coating 
of  paraffin  is  Wp  —  (WP\  —  Wc),  and  the  volume  of  the  fragment  is 

-v* 


WP  -  (WPl  -  We) 

A 


where  Dt  =  density  of  water  taken  from  the  density  tables  at  the  tem- 
perature of  the  water  when  the  weighing  was  made.  Substituting  for 
Vpi  its  value, 

„       WP  -  (WP,  -  Wc)  _  Wp-W 
Dt  0.906 

If  Wg  =  weight  of  grains  immediately  after  sample  is  crushed,  Wi  — 
Wg  =  weight  lost  or  gained  in  breaking  up  sample  into  its  separate 
grains  or  so  that  the  material  will  pass  through  a  100-mesh  sieve  in  case 
the  sand  is  very  fine.  The  difference  (W\  —  Wg)  is  usually  quite  small. 
It  can  be  made  a  negligible  quantity  by  first  using  the  Ellis  crucible9 
for  breaking  the  fragments  into  coarse  particles  and  then  using  the  agate 
crucible  for  the  finer  grinding.  In  real  fine  material,  there  is  an  error  due 
to  the  particles  taking  up  moisture,  but  in  this  work  the  error  is  inap- 
preciable or  the  above  quantity  can  be  used  as  a  correction. 

9  U.  S.  Geol.  Survey  Bull  422,  50-51. 


476  DETERMINATION   OF  PORE   SPACE 

Let 

Wg\  =  weight  of  crushed  sample,  after  drying,  at  100°  to  150°  C. 

in  an  electric  oven  for  about  1  hr.  ; 
Wk  —  weight  of  pycnometer; 
Wki  =  weight   of   water   content  of   pycnometer   at   standardized 

temperature  »; 

Wk*  =  weight  of  pycnometer  with  crushed  sample  filled  with  water; 
Da   =  density  of  water  at  temperature  t\. 
The  weight  of  water  displaced  by  the  crushed  sample  is, 

Wk>  =  Wki  -  [Wn  -  (Wk  +  W,i)] 
and  the  volume  of  the  grains  is 

._  Wks  _  Wkl  -  [Wkz  -  (Wk 


Then  the  total  volume  of  the  grains  Vtg  in  the  fragment  that  was  coated 
with  paraffin  is  found  from  the  proportion  Wg  :  W  —  Va:  Vtg',  or,  ex- 
pressed in  the  form  of  an  equation, 


W0 
Substituting  for  Vg  its  value  in  equation  (4), 

-[Wk2-  (Wk  +  W,i)]} 


W0Dtl 
Substituting  in  equation  (2)  for  V  and  Vtg  their  values, 

P  =  100  [l  -        D'W 


in  which  Wk,  Wk\,  Wc  are  experimental  constants  and  Dt  and  Da  are 
constants  found  from  the  tables  on  density  of  water  free  from  air.  These 
leave  six  quantities,  W ,  Wg,  Wk*,  Wgi,  WP)  and  WPi  to  be  found  by  weigh- 
ing. The  density  of  the  grains  free  from  moisture,  or  specific  gravity 
of  the  grains  referred  to  water  at  4°  C.  as  unity  is, 

D-W'1 

17 
For  very  accurate  determination  of  pore  space,  it  is  necessary  to  add 

a  correction  to  some  of  the  weighings  for  buoyancy  of  the  air.  In  this 
method  it  is  not  necessary  to  dry  the  fragments.  In  a  number  of  cases 
the  percentages  of  different  diameters  (of  grains)  were  found  by  sieving. 

ADVANTAGES  OF  METHODS  ADOPTED 

The  method  used  will  determine  the  pore  space  of  oil-  and  gas-bearing 
sands  in  about  one-tenth  the  time  it  takes  by  the  water  absorption 
method,  and  is  more  accurate.  In  most  cases  it  would  be  impossible  to 
determine  the  pore  space  of  the  samples  by  water  absorption  with  sufficient 


A.    F.    MELCHER 


477 


accuracy  even  for  commercial  use,  on  account  of  the  small  size  and  lack 
of  solidity  of  most  of  the  available  fragments.  Pore  space  determina- 
tions can  be  made  of  chunk  samples  that  weigh  0.1  oz.  with  an  error  of 
less  than  ±  1  per  cent.  The  pore  space  of  a  chunk  sample  weighing  0.05 
oz.,  the  grains  of  which  will  pass  through  a  No.  20  mesh  sieve  (and  most 
grains  of  oil  and  gas  sands  will  pass  through  a  mesh  of  this  size)  can  be 
determined  with  sufficient  accuracy  for  commercial  use. 

One  of  the  chief  sources  of  error  in  determining  the  pore  space  of  a 
small  sample  by  water  absorption  is  that  the  quantity  of  water  that  may 
be  taken  from  the  pores  or  left  on  the  surface  in  drying  the  sample  may  be 
a  large  percentage  of  the  total  amount  of  water  absorbed.  It  is  also 
quite  difficult  to  clean  thoroughly  oil-  and  gas-bearing  fragments  of  sands 
from  their  oil,  water,  and  gas,  as  well  as  to  saturate  them  with  water 
after  they  have  been  cleaned.  Another  difficulty  met  in  loosely  connected 
grains  of  a  sample  is  that  the  sample  may  disintegrate  when  it  is  placed 
in  water.  These  sources  of  error  and  difficulties  are  eliminated  by  the 
method  that  has  been  described. 

POROSITY  TESTS  ON  BUILDING  STONES 

The  following  are  some  determinations  of  pore  space  by  Julius 
Hirschwald10  and  show  the  variations  in  the  value  of  porosity  of  different 
methods  of  water  absorption  on  the  same  sample.  These  porosity 
tests  were  made  on  building  stones. 

Percentage  Proportion  of  Water  Absorption  to  Total  Pore  Space* 


Number  of 
Sample 

By  Method  of 
Quick  Immersion 

By  Method  of 
Gradual 
Immersion 

By    Method   of 
Gradual 
Immersion 
in  Vacuum 

By  Method  of 
Pressure  50-150 
Atmospheres 

1 

53.0 

61.3 

85.5 

100.0 

17 

45.9 

52.2 

61.1 

100.0 

11 

71.3 

81.2 

81.5 

100.0 

2 

60.9 

63.0 

99.4 

100.0 

4 

72.6 

77.2 

81.0 

100.0 

18 

53.3 

54.6 

99.5 

100.0 

16 

47.6 

49.7 

96.1 

100.0 

*  The  total  pore  space  in  these  seven  cases  is  the  same  as  the  pore  space  deter- 
mined by  the  method  of  applying  a  pressure  of  50-150  atmospheres  to  the  sample 
under  water  immediately  after  the  method  of  gradual  immersion  in  water  under  a 
vacuum  has  been  completed. 


10  Julius  Hirschwald:  Die  Prufung  der  Naturlichen  Bausteine  auf  ihre  Wetter- 
bestandigkeit.    Berlin,  190&     W.  Ernst  und  Sohn. 


478  DETERMINATION  OF  PORE  SPACE 

RESULTS  OBTAINED  FROM  PORE-SPACE  DETERMINATIONS 

Pore-space  determinations  have  been  made  from  107  chunk  samples 
of  oil  and  gas  sands,  cap-rocks,  and  shales  collected  from  Pennsylvania, 
West  Virginia,  New  York,  Ohio,  Kentucky,  Oklahoma,  Texas,  Louisiana, 
Wyoming,  and  Montana.  The  distribution  of  diameter  of  grains  of 
36  of  these  samples  have  been  determined.  The  pore  space  with  density 
and  distribution  of  diameters  of  grains  of  oil-  and  gas-bearing  sands  and 
associated  rocks  are  given  in  the  accompanying  tables.  None  of  the  pay 
sands  in  which  oil  was  found  that  had  a  porosity  less  than  10.5  per  cent, 
were  producing  sands.  The  most  probable  explanation  for  this  fact  is 
that  there  are  sufficient  fine  grains,  including  cementing  material,  be- 
tween the  larger  grains  in  these  samples  to  reduce  the  interstitial  openings 
to  a  size  sufficiently  close  to  the  subcapillary11  size  so  that  the  oil,  on 
account  of  the  resistance  it  meets  under  existing  pressure  and  tempera- 
ture, will  not  move  rapidly  enough  to  produce  in  commercial  quantities. 
A  pore  in  an  ideal  sand,  in  which  the  grains  are  uniform  spheres,  does 
not  have  a  constant  diameter  throughout  its  length,  but  varies  in  diam- 
eter and  cross-section,  passing  continuously  from  a  minimum  to  a 
maximum  cross-section. 

Professor  Slichter12  has  shown  that  the  flow  of  water  through  a  sand 
may  be  reckoned  as  passing  through  an  ideal  sand,  the  pores  of  which 
are  continuous  tubes  of  the  minimum  size.  This  reduction  of  the  cross- 
section  of  the  pore  to  the  minimum  for  the  flow  of  the  oil  would  make  the 
size  of  the  pore  approach  much  closer  to  the  subcapillary  than  at  first 
it  would  appear  from  the  diameter  of  the  grains.  On  the  other  hand, 
the  grains  of  sand  can  be  of  such  a  shape  and  laid  down  in  such  a  way  that 
the  width,  or  diameter,  of  the  pores  at  places  are  sufficiently  close  to  the 
subcapillary  to  interfere  materially  with  production.  The  production 
in  such  a  case  might  not  be  sufficient  for  commercial  quantities,  even 
when  the  well  is  repeatedly  shot. 

In  Ohio,  there  are  four  wells  of  which  production  or  non-production 
are  given.  Plots  of  the  sands  of  these  wells  are  shown  in  Fig.  3,  in  which 
the  percentages,  by  weight,  are  plotted  as  ordinates  and  the  diameters 
of  grains  are  plotted  as  abscissas.  The  depths  of  the  sands  from  which 
samples  5,  7,  and  10  were  obtained  are  about  the  same,  the  depth  of  the 
sand  from  which  sample  16  was  procured  is  not  given,  but  is  probably 
about  the  same  as  the  others.  Sample  10  has  a  pore  space  of  16.9  per 
cent.,  the  grains  of  its  maximum  column  are  larger  in  diameter  than 

11  A  subcapillary  tube  is  one  in  which  molecular  attraction  extends  across  the 
tube;  the  average  size  of  such  a  tube,  as  determined  experimentally  by  different 
physicists,  is  about  0.00002  mm.  in  diameter. 

12  C.  S.  Slichter:  Theoretical  Investigation  of  the  Motion  of  Groundwater.     U.  S. 
Geol.  Survey,  19th  Ann.  Kept.  (1899)  Pt.  2,  305-323. 


A.    F.    MELCHER  479 

the  grains  of  the  maximum  column  of  samples  7  and  16,  and  are  about  the 
same  diameter  as  the  grains  of  the  maximum  column  of  sample  5.  The 
well  from  which  sample  10  was  collected  had  an  initial  production  of 
400  bbl.  Sample  5  had  a  pore  space  of  13.1  per  cent,  and  the  well  from 
which  this  sample  was  obtained  had  an  initial  production  of  80  bbl. 
Sample  16  had  a  pore  space  of  16.8  per  cent,  and  has  its  maximum  column 
at  a  much  smaller  diameter  of  grain  than  samples  5  and  10,  and  the  well 
from  which  this  sample  was  collected  had  an  initial  production  of  100  bbl. 
Sample  7  had  a  pore  space  of  4.7  per  cent,  and  its  maximum  column  had 
a  small  diameter  of  grain;  the  well  from  which  this  sample  was  taken 
was  non-productive. 

RELATION  OF  PORE  SPACE  TO  PRODUCTIVITY  OF  POOL 

Pore  space  is  undoubtedly  one  of  the  several  factors  that  control 
production  from  an  oil  or  gas  pool.  Professor  Slichter13  also  has  shown 
that  if  two  samples  of  the  same  sand  are  packed,  one  sample  so  that  its 
porosity  is  26  per  cent,  and  the  other  sample  so  that  its  porosity  is  47 
per  cent.,  the  flow  through  the  latter  sample  will  be  more  than  seven 
times  the  flow  through  the  former.  If  the  two  samples  of  the  same  sand 
had  been  packed  so  that  their  porosities  had  been  30  per  cent,  and  40 
per  cent.,  respectively,  the  flow  through  the  latter  sample  would  have 
been  about  2.6  times  the  flow  through  the  former.  He  states  that 
"These  facts  should  make  clear  the  enormous  influence  of  porosity  on 
flow,  and  the  inadequacy  of  a  formula  of  flow  that  does  not  take  it  into 
account." 

Comparison  of  the  production  of  one  oil  or  gas  pool  with  another 
or  of  one  oil  well  with  another,  from  a  comparison  of  their  physical  con- 
stants and  factors,  is  very  similar  to  the  comparison  of  two  unknown 
quantities,  each  of  which  is  made  up  of  an  equal  number  of  factors.  It 
is  at  once  apparent  that  the  more  known  factors  there  are  of  each,  the 
more  nearly  can  they  be  compared  or  estimated.  In  this  same  manner 
can  the  production  of  an  oil  or  gas  pool,  or  oil  and  gas  well,  be  estimated 
or  compared,  and  the  more  factors  known  the  closer  can  the  production  be 
estimated  or  compared  with  a  known  production  of  a  pool  or  well  of 
known  physical  factors.  In  three  out  of  four  samples  where  the  quantity 
of  combustible  matter  burned  out  of  the  sample  of  sand  amounted  to  3 
per  cent,  or  less  by  volume,  the  well  from  which  the  sample  was  taken 
produced  salt  water  with  the  oil;  see  Table  1. 

CONCLUSIONS 

A  method  has  been  established  that  will  determine  the  pore  space  of 
very  small  fragments  of  oil  and  gas  sands  and  determine  the  pore  space 
accurately.  None  of  the  pay  sands  in  which  oil  was  found,  if  the  pore 

*8  C.  S.  Slichter:  Op.  tit.,  323. 


480 


DETERMINATION   OF   PORE   SPACE 


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Per  Cent.,  by  Volume,  of  Comb 
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A.    F.   MELCHER 


481 


DIAMETER       OF      GRAINS      IN      MILLIMETERS 


.07*    .104    .147    .208   .295    .417   .833    1.651 


BEREA  SAND  ,  WOODSFI ELD,  OHIO 
Sa/np/e  from  tve//  that  produced  oi/ and  very  /iff/e  ^afc  Hater 

POROSITY  w-.e 


O      .074    J04     .147    .208  .295    .417    .833  (£61 


BRADFORD    PAY  3AND  ,  PA.. 

POROSITY  17.  a 


KEENER    SAND,  WOODSFIELD,  OHIO 
aoropte  from  tve//  tfiof-yi'e/dedgas.  otfarrdsa/t  nater 
POROSITY    12..7 


BEREA  SAND,  WOODSFIELD, OHIO 
from  weft  fftaf-  j 

ITV    10.  S 


BEREA   SAND,  WOODSFIELD,  OHIO 
•Samp/a   from  productive  o/7  we// 
POROSITY   11.0 


DEVELOPERS  OIL  AND  6AS  CO,  FTrROLIA,TEXAS 
POROSITY    IS.S 


'     COAL  RIVER   NO.  4  DAWES  .W.VA. 
POROSITY    6.1 


BEREA  SAND.CHASEVILLE,  OHIp 
Sample  from   ncr>-producfir&  n>e// 
POROSITY    4.7 


BEREA  SAND.  ARMSTRONG    MILLS, OHIO 

fhgmenr  from  Me//  Hfr&r  hod '  mMal 'production  of/OO  t 

POROSITY    16.8 


KEENER    SAND,  JERUSALEM ,  OHIO 
/nifta/  product/on  <4OOob&. 
POROSITY    16.9 


BIS  INJUN  SAND,  LEWISVILLE.OHIO 
/nitio/  production  BO  obis 
POROSITY  13.1 


COAL  RIVER  NO.  I    DAWES,  W.VA. 
POROSITY  4.8 


IO4     .147    .206    .296    .417    .833   1.651 


CABIN  CREEK  NO. 92    DAWES, W.VA. 
'    POROSITY  IB.  7 


.074-    .104    .147    .208    .295   417    .833  1.651 


COAL  RIVER  NO.  4    DAWES,  W.VA. 
POROSITY  19.7  i 


FIG.  3. — PERCENTAGE  DISTRIBUTION  OP  DIAMETER  OP  GRAINS  OP  ELEVEN  OIL- 
BEARING   SANDS,  ONE  NON  PRODUCTIVE  SAND  AND  TWO  CAP-ROCKS. 


VOL.  LXV. — 31. 


482 


DETERMINATION   OF   PORE    SPACE 


space  was  less  than  10.5  per  cent.,  were  producing  sands.  A  study  of 
samples  10, 16,  5,  and  7  in  Fig.  3,  in  connection  with  the  corresponding 
pore  spaces  and  diameters  of  grains  in  the  maximum  columns  of  the 
different  samples  suggests  the  conclusion  that  production  is  dependent 
on  both  pore  space  and  size  of  grains,  other  factors  being  equal. 

Data  already  obtained  indicate  that  results  of  physical  experiments 
involving  the  constants  and  factors  stated  in  this  paper  are  not  only  of 
scientific  value  but  can  also  be  used  in  connection  with  the  most  efficient 
methods  of  recovery  of  oil  and  gas;  namely,  in  the  valuation  of  oil  and 
gas  fields,  in  the  possible  application  of  various  methods  of  oil  extraction 
in  fields  where  the  normal  flow  is  not  sufficient  to  justify  financially  the 
continuation  of  the  well,  in  plugging  off  water,  in  spacing  and  rate  of 
pumping  of  wells,  in  avoiding  interference  of  wells  with  one  another, 
in  recognizing  the  nature  and  texture  of  oil-bearing  beds,  which  will 
respond  to  shooting,  and  where  shooting  will  be  detrimental. 


TABLE  2. — Total  Pore  Space  with  Density  and  Percentage  Distribution 

of  Diameters  of  Grains  of  Gas-bearing  Sands  from   Mexia- 

Groesbeck  Gas  Field,  Limestone  Co.,  Tex.* 


« 

<N 

M 

_- 

^ 

dg 

d  g 

,_, 

dg 

og 

6 

dfl 

d  fl 

•5  g 

£  Q 

d 

fc 

g  X 

£  § 

"o'« 

•81 

& 

|'»d 

||« 

1 

•glrf 

fl3 

1*6 

l^d 

1 

rt°° 

*ftz 

£ 

CCQ 

o^ 

M^"15 

&~* 

0 

Pore  space,  per  cent,  by  volume. 

13.2 

10.7 

16.6 

34.2 

37.7 

25.7 

22.8 

34.4 

Total  weight,  in  grams  

0.847 

1.557 

0.310 

1.258 

0.843 

4.766 

0.845 

3.274 

Density    of    grains    free    from 

moisture,    or    specific    gravity 

referred  to  water  at  4°  C.  as 

unity  

2.76 

2.73 

2.70 

2.68 

2.73 

Diameters     from     0.833-0.417, 

mm    per  cent 

0.4 

2.4 

0.3 

0.3 

3.5 

10  ft 

0  417-0  295  mm.,  per  cent  

1.4 

8.1 

2.3 

2.2 

10.4 

1U  .  O 

20.1 

0.295-0.208  mm.,  per  cent  

9.2 

21.5 

5.6 

5.4 

16.2 

17.1 

0.208-0.147  mm.,  per  cent  

33.3 

29.2 

39.0 

38.9 

26.6 

13.6 

0.147-0.104  mm.,  per  cent.  

40.1 

29.2 

40.2 

42.0 

25.3 

14.1 

0  104—0  074  mm    per  cent  .    . 

6.2 

4.8 

5.9 

4.7 

9.7 

8.5 

0  074—0  000  mm    per  cent 

9.5 

4.8 

6.6 

6.4 

8.4 

15.8 

Total 

100.1 

100.0 

99.9 

99.9 

100.  1 

100.0 

*    These  samples  were  collected  by  Mr.  George  C.  Matson. 


In  Table  2,  the  Clark  No.  1  sample  contains  a  small  amount  of  iron. 
The  distribution  of  diameters  of  the  Rawls,  Clark,  and  Kendrick  sands 
was  determined  from  a  mixture  of  the  two  samples.  The  two  determina- 
tions of  Clark  No.  1  are  duplicate  measurements  of  the  same  sample. 
Cargile  No.  1  consists  largely  of  very  small  particles  cemented  together; 


A.    F.    MELCHER 


483 


nearly  all  of  this  material  would  pass  through  the  200-mesh  sieve  (0.074- 
mm.  diameter  of  grain)  without  breaking  the  particles.  Kendrick 
Nos.  1  and  2  contain  a  small  percentage  of  cemented  material,  but  the 
remaining  portion  of  Kendrick  Nos.  1  and  2,  and  all  of  Rawls,  Welsh, 
and  Clark,  consist  of  well-defined  individual  grains. 

TABLE  3. — Total  Pore  Space  with  Density  and  Percentage  Distribution  of 

Diameters  of  Grains  of  Gas  and  Oil-bearing  Sands  from  Developers 

Oil  &  Gas  Co.,  Petrolia,  Tex.* 


fctfift     -^rV' 

Well  No.  5, 
Oil-bearing 
Sand 

Beatty  Well 
No.  1  Gas 
Sand 

Byerswell 
Specimen 
No.  1  Gas 
Sand 

Byerswell 
Specimen 
No.  2  Gas 

Sand 

Pore  space,  per  cent,  by  volume 
Total  weight,  in  grams  

18.5 

17  725 

21.7 
8  522 

26.6 
22  798 

24.9 
19  897 

Density    of    grains    free    from 
moisture,  or  specific  gravity  re- 
a  f  erred  to  water  at  4°  C.  as  unity 
Diameters     from     0.833-0.417 
mm    per  cent. 

2.65 
0  2 

2.64 
0  01 

2.66 
0  01 

0.417-0.295  mm.,  per  cent  

8  2 

0  3 

0  02 

0.295-0.208  mm.,  per  cent  

45.8 

23.0 

0.1 

0.208-0.147  mm.,  per  cent  

29  5 

55  6 

31.5 

0.147-0  104  mm.,  per  cent. 

12  5 

15  8 

50  0 

0.104-0.074  mm.,  per  cent  

1.8 

2.6 

9.6 

0.074-0  000  mm.,  per  cent. 

2  0 

2  7 

8  8 

Total  

100.0 

100.0 

100.0 

*  These  samples  were  collected  by  Mr.  E.  W.  Shaw. 


TABLE  4. — Total  Pore  Space  and  Density  of  Grains  of  Oil  Sands  and  Asso- 
ciated Rocks  from  Butler  and  Zelienople  Quadrangles,  Pennsylvania* 


No.  1 

No.  2 

No.  3 

No.  4 

No.  5 

No.  6 

No.  7 

No.  8 

Pore   space,    per 

cent,  by  volume. 

8.0 

8.5 

22.2 

14.5 

10.4 

45 

7.3 

5.5 

Total  weight  of 

sample,  in  grams 

48.281 

14.840 

5.770 

9.331 

21.994 

9.637 

9.811 

6.493 

Density  of  grains 

free  from  mois- 

ture, or  specific 

gravity  referred 

to  water  at  4°  C. 

as  unity  . 

2.68 

2.65 

2.67 

2.67 

2.66 

2.66 

2.65 

2.66 

*  These  samples  were  collected  by  Mr.  G.  B.  Richardson. 


484 


DETERMINATION   OF   PORE    SPACE 


In  Table  3,  the  distribution  of  diameters  of  the  Byerswell  sand  was 
determined  from  a  mixture  of  the  two  samples.  Both  samples  of  the 
Developers  Oil  &  Gas  Co.  Well  No.  5,  and  Beatty  Well  No.  1,  contained 
a  small  quantity  of  magnetite.  The  Developers  Well  No.  5  consisted  of 
the  largest  size  grains,  a  maximum  percentage  being  of  a  diameter  between 
0.208  mm.  and  0.295  mm.  The  Beatty  sample  gave  a  maximum  per- 
centage of  grains  between  0.147  and  0.208  mm.  The  Byerswell  sand 
consisted  of  the  smallest  grains  of  the  three  samples,  the  maximum 
percentage  being  between  0.104  mm.  and  0.147  mm,  All  three  samples 
consisted  of  well-defined  individual  grains. 


TABLE  5. — Total  Pore  Space  in  Oil  and  Gas-bearing  Sands  and  Associ- 


No.  1 

No.  2 

No.  3 

No.  4 

No.  5 

No.  6 

11  2 

7  0 

12  7 

12  7 

13  1 

11  3 

10.8 
53.239 

10  733 

17  706 

40.819 

41  120 

8  970 

Density  of  grains  free  from  moisture,  or  specific 
gravity  referred  to  water  at  4°  C.  as  unity  

31.974 
2  647 

2.675 

2  659 

2  646 

2  654 

y'Y 
2  651 

Diameters  greater  than  1.651  mm.,  per  cent  

20.4 

O.d 

Diameters  from  1.651-0.833  mm.,  per  cent  

56  4 

31.8 

0.833-0.417  mm.,  per  cent  

14.7 

45.2 

0.417-0.295  mm.,  per  cent  

2.4 

2.5 

10.3 

0  .  295-0  .  208  mm.,  per  cent  

8.3 

29.4 

1.7 

5.0 

0.208-0.  147  mm.,  per  cent  

48.0 

50.6 

13.1 

53.3 

1.6 

3.6 

0  147-0  104  mm    per  cent 

36  8 

26  1 

63  3 

10  1 

1  i 

1  7 

0  104-0  074  mm    per  cent 

4  9 

3  7 

8  6 

1.7 

0  7 

0  4 

0  .074-0  .000  mm.,  per  cent  

10.3 

11.3 

15.0 

3.2 

0.9 

1.2 

Total  

100.0 

100.0 

100.0 

100.1 

100.0 

99.8 

Only  one  sample,  No.  4,  showed  the  presence  of  oil.  It  is  quite  certain  that  none 
of  the  other  samples  belong  to  the  oil-bearing  sands. 

No.  1,  Fourth  Sand,  Speechley  Pool.  Concord  Township,  Butler  Co.,  Butler 
Quadrangle. 

No.  2,  Third  Sand,  Evans  City  Pool,  Forward  Township,  Butler  Co.,  Zelienople 
Quadrangle. 

No.  3,  Snee  Sand,  Petersville  Pool,  Conoquenessing  Township,  Butler  Co.,  Zelien- 
ople Quadrangle. 

No.  4,  "Clover  seed,"  Top  of  Fourth  Sand,  Haysville  Pool,  Fairview  Township, 
Butler  Co.,  Butler  Quadrangle. 

No.  5,  Fourth  Sand  (hard),  Haysville  Pool,  Fairview  Township,  Butler  Co., 
Butler  Quadrangle. 

No.  6,  100-ft.  Sand,  Evans  City  Pool,  Forward  Township,  Butler  Co.,  Butler 
Quadrangle. 

No.  7,  100-ft.  Sand,  Evans  City  Pool,  Forward  Township,  Butler  Co.,  Butler 
Quadrangle. 

No.  8,  Fourth  Sand,  Haysville  Pool,  Fairview  Township,  Butler  Co.,  Butler 
Quadrangle. 


A.    F.    MELCHER 


485 


No.  1.  Berea  sand;  depth  2050±  ft.;  from  Well  No.  1  on  the  M.  O.  Huth  farm  near  Woodsfield, 
Center  Twp.,  Monroe  County,  Ohio;  fragment  from  a  productive  oil  well. 

No.  2.  Berea  sand;  depth  1807-1829  ft.;  from  Well  No.  2  on  the  N.  H.  Burkhead  heirs  farm  near 
Woodsfield,  Center  Twp.,  Monroe  County,  Ohio;  hard  densely  cemented  fragment  from  a  Berea  gas  well. 

No.  3.  Berea  sand;  depth  1440 ±  ft.  sand  sent  by  Larrick  Bros,  from  Well  No.  2,  J.  W.  Steel  farm, 
near  Chaseville,  Sec.  26,  Buffalo  Twp.,  Noble  County,  Ohio;  hard  densely  cemented  fragment  from  a 
non-productive  well. 

No.  4.  Keener  sand;  depth  1539-1570  ft.;  near  the  Huth  farm,  Woodsfield,  Center  Twp.,  Monroe 
County,  Ohio;  from  a  bed  that  yielded  gas,  oil,  and  salt  water. 

No.  5.  "Big  Injun"  sand;  depth  1460-1470±  ft.;  well  No.  2,  A.  C.  Weber,  Lewisville,  Summit 
Twp.,  Monroe  County,  Ohio;  from  a  bed  that  yielded  gas,  oil,  and  salt  water.  Initial  daily  yield  of 
well  was  80  bbl.  of  oil. 

No.  6.  Keener  sand;  depth  1220-1259  ft.;  from  well  No.  5  on  the  G.  W.  Kysor  farm  near  Coats 
Station,  Center  Twp.,  Monroe  County,  Ohio;  fragment  of  sandstone  from  a  bed  from  which  oil  and 
salt  water  were  pumped. 


ated  Rocks,  with  Diameter   and   Density  of  the   Component  Grains  * 


No.  7 

No.  8 

No.  9 

No.  10 

No.  11 

No.  12 

No.  13 

No.  14 

No.  15 

No.  16 

4.7 

9.7 

11.0 

17.7 

14.5 

18.4 

10.5 

11.0 

13.0 

11  3 

14.7 

17.1 

12.4 

15.0 

15.9 

17.4 

16.238 

14.090 

5.765 

41.482 

19.693 

8.446 

28.591 

5.057 

3.819 

1.956 

36.412 

60.867 

4.309 

28.900 

43.213 

30.979 

2.665 

2.727 

2.705 

2.653 

2.649 

2.647 

2.649 

2.662 

2.731 

2.658 

2.698 

2.682 

0.8 

1.9 

23.5 

0.2 

0.8 

41.1 

34.4 

2.6 

8.5 

16.6 

47.2 

30.1 

78.9 

70.8 

18.3 

3.4 

5.1 

12.4 

4.6 

12.9 

30.3 

0.3 

13.8 

2.7 

3.6 

2.6 

29.6 

3.2 

28.8 

25.4 

36.0 

11.2 

1.7 

1.7 

1.4 

30.1 

18.7 

1.4 

20.5 

0.4 

54.3 

38.2 

37.6 

11.0 

1.0 

0.9 

0.9 

10.0 

48.6 

1.0 

10.1 

56.8 

11.4 

9.6 

26.0 

12.0 

0.5 

0.4 

0.4 

10.3 

12.6 

0.4 

4.1 

20.0 

2.9 

16.2 

36.4 

15.4 

0.6 

0.3 

0.6 

15.5 

20.1 

1.8 

6.2 

22.8 

5.8 

100.0 

100.0 

99.9 

100.1 

100.0 

100.0 

100.1 

100.0 

100.0 

100.0 

100.0 

100.1 

*  These  samples  were  collected  in  Ohio  by  Mr.  R.  Van  A.  Mills  and  Mr.  D.  Dale  Condit. 


No.  7.  Berea  sand;  depth  1535±  ft.;  Chaseville,  Seneca  Twp.,  Noble  County,  Ohio;  hard,  densely 
cemented  fragment  from  a  non-productive  well. 

No.  8.  Hard,  bluish-gray  shale  overlying  the  Keener  sand;  depth  1445  ft.;  J.  R.  Scott  farm,  Jeru- 
salem, Sunsbury  Twp.,  Monroe  County,  Ohio. 

No.  9.  Light  bluish-gray  shale,  overlying  the  Keener  sand;  depth  1475 ±  ft.;  Hinderlong  farm, 
Miltonsburg,  Malaga  Twp.,  Monroe  County,  Ohio. 

No.  10.  Keener  sand;  depth  1451-1469  ft.;  Well  No.  2;  J.  R.  Scott  farm,  Jerusalem,  Sunsbury 
Twp.,  Monroe  County,  Ohio;  loosely  cemented  sandstone  from  productive  bed,  initial  daily  production 
of  oil  from  well  was  approximately  400  bbl. 

No.  11.  Berea  sand;  depth  1890-1920±  ft.;  Well  No.  5;  Henry  Herdershot  farm,  Monroe  County, 
Ohio;  fragment  from  productive  bed;  well  yielded  both  gas  and  oil. 

No.  12.  Berea  sand;  depth  1500±  ft.;  McLaughlin  Well  No.  5;  Chaseville,  Seneca  Twp.,  Noble 
County,  Ohio;  fragment  from  productive  bed;  well  yielded  both  oil  and  gas,  with  practically  no  salt 
water. 

No.  13.  Gas  sand;  depth  1350-1355  ft.;  George  Reem-Schneider  farm,  Sec.  11,  Malaga  Twp., 
Monroe  County,  Ohio;  fragment  from  a  bed  that  yielded  gas. 

No.  14.  "Big  Injun"  sand;  depth  1460-1500±  ft.;  Well  No.  1,  Ben  Butts  farm,  Lewisville,  Summit 
Twp.;  Monroe  County,  Ohio;  fragment  from  a  bed  that  yielded  oil  and  salt  water. 

No.  15.  Berea  sand;  depth  2140-2160 ±  ft.;  Well  No.  4,  Taylor  heirs  farm,  Woodsfield,  Center 
Twp.,  Monroe  County,  Ohio;  fragment  from  productive  bed;  well  yielded  oil  with  very  little  salt  water. 

No.  16.  Berea  sand;  Shepherd  farm,  Armstrong  Mills,  Belmont  County,  Ohio;  fragment  from  a 
productive  bed;  initial  daily  production  of  well  was  100  bbl. 


486 


DETERMINATION   OF   PORE   SPACE 


TABLE   6. — Physical   Properties   of  Chattanooga   Black  Shale  from    the 
Irvine  Oil  Field,  Irvine,  Ky.  * 


Pore  Space,  Per  Cent, 
by  Volume 

Total  Weight  of  Sam- 
ple, in  grams 

Density  of  Grains  Free 
from  Moisture,  or 
Specific  Gravity 
Referred  to  Water 
at  4°  C.  as  Unity 

Trial  No.  1 

7   6 

34  646 

2  57 

Trial  No.  2  

7  4 

45  670 

2.57 

*  These  determinations  of  porosity  have  been  previously  published.  See  Eugene 
W.  Shaw:  The  Irvine  Oil  Field.  U.  S.  Geol.  Survey  Bull.  661-D,  190.  Mr.  Shaw 
collected  the  samples. 

TABLE  7. — Total  Pore  Space  and  Density  of  Grains  of  Oil  and  Gas  Sands 
and  Associated  Rocks  from  Wyoming  and  Montana* 


Name  and  Location 
of  Sand 

Pore  Space 
Per    Cent,    by 
Volume 

Density  of 
Grains  Free 
From  Mois- 
;ure,  or  Specific 
Gravity  Re- 
ferred to 
Water  at 
4°  C.  as 
%  Unity 

1.  Wall  Creek  sand,  Pine  Mts.,  Wyo  {  i?!a|  * 

3.6 

2.659 

3.2 

2.  Peay  sand,  Stump  triangle  station,  Big  Horn  f  Trial  1 

5.1 

2.651 

Mts                                                                   1  Trial  2 

5.1 

3.  Wall  Creek  (Peay)  S.  S.  Jack  Creek,  Mont  

5.0 

2.710 

4.  Torchlight  S.  S.  about  2>£  mi.  east  of  Grey-  f  Trial  1 

28.6 

2.634 

bull,  Wyo  1  Trial  2 

30.1 

28.9  , 

5.  Wall  Creek,  S.  S.,  Calcareous  layer.     From  east  side 

Powder  River  House,  Wyo.,  10  mi.  west  Salt  Creek.  .  . 

7.6 

2.675 

f  Trial  1 

25.8 

2.640 

6.  The  main  oil  sand  of  Salt  Creek  field,  Wyo.  .  \  ^  .  }  1 
[  l  rial  z 

25.8 

7.  Shannon  sandstone,  %  mi.  northeast  of  town  f  Trial  1 

26.9 

2.667 

of  Salt  Creek,  Wyo  1  Trial  2 

26.6 

8.  Wall  Creek  S.  S.,  10  mi.  west  of  Salt  Creek,  f  Trial  1 

19.9 

2.650 

Wyo.     Lower  Ledge  (full  of  cleavage  planes)  \  Trial  2 

20.9 

9.  Peay  S.  S.  Jack  Creek,  Mont  I  ^r!a}  \ 

18.7 

2.639 

[  1  rial  2 

18.5 

10    Peay  S.  S.  Greybull  oil  field  Wyo.                   j  Tr!a!  l 

28.6 

2.655 

28.6 

These  samples  were  collected  by  Mr.  Carroll  H.  Wegemann. 


A.    P.    MELCHER 


487 


TABLE  8. — Total  Pore  Space  with  Density  and  Percentage  Distribution  o] 

Diameters  of  Grains  of  Oil-  and  Gas-bearing  Sands  and  Associated 

Rocks  from  Dawes,  W.  Va.  * 


Ohio  Cities  Gas  Co. 

No.  1 
Coal 
River 
No.  1, 

Rock 

No.  2 
Coal 
River 
No.  4, 
Cap 
Rock 

No.  3  Coal  River,  No.  4  Pay 
Sand 

No.    4,    Cabin 
Creek  No.  92 
Pay  Sand 

Nr.5 
Kelley 
Creek, 
W.Va. 
Gray 
(Wier) 
Sand. 
Only 
Well  on 
this 
Creek 

Speci- 
men 1 

Speci- 
men 2 

Speci- 
men 3 

Speci- 
men 4 

Speci- 
men 1 

Speci- 
men 2 

Pore    space,    per    cent,    by 
volume  .    .  . 

4.8 
12.707 

2.656 

30.6 
34.7 
13.7 
8.8 

12.1 
99.9 

6.1 
6.730 

2.636 

0.5 
48.7 
30.3 

7.7 

12.8 
100.0 

21.7 
5.030 

2.672 

20.6 
17.1 
14.9 

47.4 
100.0 

20.1 
3.479 

18.8 
4.172 

16.6 
5.964 

18.0 
30.933 

2.664 

11.0 
39.7 
28.4 
13.1 
3.7 

4.1 
100.0 

19.4 
38.285 

13.7 
1.347 

2.663 

3.2 
25.3 
25.8 
15.1 

30.6 
100.0 

Total  weight,  in  grams  ...    . 

Density  of  grains  free  from 
moisture,  or  specific  gravity 
referred  to  water  at  4°  C.  as 
unity  

Diameters  from  0.295-0.417 
mm.,  per  cent  

0.208-0.295  mm.,  per  cent.  .  . 
0.147-0.208  mm.,  per  cent..  . 
0.104-0.147  mm.,  per  cent..  . 
0.074-0.104  mm.,  per  cent..  . 
Diameters    less    than    0.074 
mm.,  per  cent  

Total  

*  These  samples  were  collected  by  Mr.  E.  W.  Shaw. 

TABLE  9. — Total  Pore  Space  and  Density  of  Grains  of  Sand  from  Bartles- 

ville,  Okla.* 


(i) 

Bartlesville 
Pay  Sand, 
Bartlesville, 
Okla.,  Skelton- 
Moore  Well 
No.  11,  Speci- 
men 1 

(1) 

Bartlesville 
Pay  Sand, 
Bartlesville, 
Okla.,  Skelton- 
Moore  Well 
No.  11,  Speci- 
men 2 

(2) 
Outcropping 
Ledge  of 
Sandstone 
From  Same 
Section, 
Specimen  1 

C2>, 

Outcropping 
Ledge  of 
Sandstone 
From  Same 
Section, 
Specimen  2 

Pore  space,  per  cent,  by  volume 
Total  weight,  in  grams  

16.6 

7.258 

2.643 

6.0 
12.3 
46.1 
18.3 
6.6 

10.0 
99.3 

16.1 

8.464 

16.4 
9.264 

2.672 

5.3 
27.9 
39.6 
16.4 
4.6 

6.2 
100.0 

17.7 
6.079 

Density  of  grains  free  from 
moisture,  or  specific  gravity  re- 
ferred to  water  at  4°  C.  as 
unitv.  . 

Diameters  from  0.295-0.417 
mm.,  per  cent  

0.208-0.295  mm.,  per  cent. 

0.147-0.208  mm.,  per  cent  
0  104-0.147  mm.,  per  cent  
0.074-0.101  mm.,  per  cent. 

Diameters  less  than  0.074  mm., 
per  cent  

Total  

*  These  samples  were  collected  by  Mr.  G.  B.  Richardson. 


488 


DETERMINATION   OF   PORE   SPACE 


TABLE  10. — Total  Pore  Space  and  Density  of  Grams  of  Gas-bearing  Sands 
and  Associated  Rocks  from  Shreveport,   La.  * 


Name  and  Location 
of  Sand 

Pore  Space, 
Per  Cent, 
by  Volume 

Total  Weight 
of  Sample,  in 
Grams 

Density  of 
Grains  Free 
From  Mois- 
ture, or  Specific 
Gravity  Re- 
ferred to  Water 
at  4  C.  as 
Unity 

1.  Woodbine  sand,  Butler  well  

17  4 

17   512 

2  733 

2.  Tooke  and  Burke,  No.  1 

29  1 

4  068 

2  681 

3.  Pay  sand,  rare  sample,  Curtis  No.  1  .  . 

24  3 

1  942 

2  647 

4.  Greenish  shale,  just  above  pay  sand  of 
Curtis  No.  1  

22  6 

1  628 

2  717 

5.  Reddish  shale,  just  above  pay  sand  of 
Curtis  No.  1  

20  0 

0  870 

2  769 

6.  Flournoy,  No.  1  

37  7 

7  300 

2  700 

7.  McCutcheon  fee  No.  1  

22  2 

4  752 

2  691 

8.  Henderson  and  Hester,  two  deter-     ,  . 
minations,  very  fine  sand,  almost     „! 
the  appearance  of  shale.  .    . 

31.1 
32  6 

0.808 

0  772 

2  725 

9.  Independent  Ice  Co.,  fee  No.  1,  close  to 
above  

36  7 

8  705 

2  688 

10.  McCormick  fee,  Well  No.  155 

25  3 

4  876 

2  728 

11.  McCullough  fee,  No.  1  I  ^ 

17.8 

37.106 

12.  Stoer,  fee  No.  1  

20.3 
14  6 

25.582 
12  003 

3.314 
2  693 

13.  Vivian  field,  Conlay  No.  5 

22  5 

2  776 

2  640 

14.  May  Oil  Co.  No.  3  on  S.  W.  Gas  & 
Electric  Co.   No.   2.     Two  deter-    (a) 
minations  '.  (b) 

28.5 
26  0 

2.313 
3  897 

2  591 

15.  Monroe  gas  pay  sand.     Smith  Nos.   1 
and  2  

27  2 

2  448 

2.672 

16.  Stringfellow  fee  No.  2  

9  4 

3  647 

2  705 

17.  Christian  No.  4.  .                                 1  [a] 

9.6 

1.160 

((b) 
18.  Hodges  ward  1,  sample  of  shale,  deep 
gas  sand  

8.8 
16.9 

1.137 
6.931 

2.662 
2.752 

19.  Sample  of   sandstone   containing   some 
shale,  same  well  as  No.  18  

19.7 

23.348 

2.673 

20.  Sample  from  same  well  as  No.  18,  dark 
gray  sand  

23  7 

11  812 

2  716 

21.  Sample  from  same  well  as  No.  18,  light 
reddish  gray  sand  

20  4 

15  520 

2.654 

*  These  samples  were  collected  by  E.  W.  Shaw. 

After  grinding  until  they  passed  through  the  100-mesh  sieve, 
the  samples  were  washed  in  petroleum  ether.  The  sample  that  gave  7.6 
per  cent,  porosity  was  washed  twelve  times;  the  other  was  washed 
eighteen  times  A  washing  consisted  of  covering  the  sample  with 


A.    F.   MELCHER 


489 


petroleum  ether,  letting  it  boil  for  about  15  min.,  and  then  decanting 
off  the  petroleum  ether.  Petroleum  ether  was  again  poured  over  the 
sample  and  then  poured  off;  the  process  was  then  repeated.  The  final 
porosity  of  each  sample  was  found  to  be  8  per  cent. 

The  separated  grains  of  the  shale  passed  through  the  300-mesh  sieve. 
A  3-gm.  sample  of  the  shale  was  passed  through  a  100-mesh  sieve  and 
then  boiled  for  20  min.  in  concentrated  hydrochloric  acid.  The  porosity 
determined  from  the  powder  thus  treated  is  8  per  cent.,  the  same  as  was 
obtained  by  boiling  in  petroleum  ether  Another  3  gm.  sample  was 
passed  through  the  100-mesh  sieve  and  heated  20  min.  in  a  Bunsen  flame; 
the  porosity  determined  from  this  final  product  is  19.6  per  cent.  The 
specific  gravity  of  the  powder  thus  treated  is  2.59,  and  a  solid  cubic 
foot  of  it  would  weigh  161.69  Ib.  A  cubic  foot  of  the  shale  with  the  19.6 
per  cent,  of  pore  space  emptied  in  the  way  outlined  would  weigh  130  Ib. 

In  Table  7,  the  second  determination  of  sample  No.  4  is  known  to  be 
slightly  erroneous.  The  value,  28.9,  is  a  weighted  mean  in  which  the 
first  observation  is  given  a  weight  equal  to  four  times  the  second.  No  oil 
was  found  in  any  of  the  samples,  when  they  were  tested  in  the  flame. 

Two  tests  of  each  sample  have  been  made.  No  indications  of  oil 
were  found  by  heating  specimens  1  and  2  of  pay  sand  No.  1  in  a  platinum 
crucible. 

After  a  fragment  of  the  Bradford  pay  sand,  Table  11,  weighing  11.817 
gm.  was  heated  in  a  platinum  crucible  by  a  Bunsen  flame  until  all  organic 
matter  and  moisture  were  expelled  it  weighed  11.330  gm.  The  volume 
of  the  fragment  equaled  4.255  G.XJ.  If  0.80  is  the  specific  gravity  of  the 
oil,  the  volume  of  the  organic  matter  (mainly  oil)  is  0.608  c.c.  Then  the 
per  cent,  of  the  total  volume  of  the  fragment  burned  is  14.3.  Taking 
0.84  as  the  density  of  the  oil,  the  per  cent,  of  the  total  volume  of  the 
fragment  burned  is  13.6. 

TABLE  11. — Total  Pore  Space  and  Density  of  Grains  of  Bradford 
Oil-bearing  Sand  and  Medina  Sand  * 


Density  of 
Grains  Free 

Pore  Space, 
Per  Cent. 
by  Volume 

,  Total  Weight 
of   Sample,   in 
Grams 

From  Mois- 
ture, or  Spe- 
cific Gravity 
Referred  to 

Water  at  4°  C. 

as  Unity 

Medina 

sand,  Niagara  Gorge,  Niagara, 

(a) 

7.8 

24.363 

N  Y. 

Two  determinations 

(M 

8  0 

15  126 

2  657 

Bradfor< 

I  pay  sand,  Minaid  Run  Oil  Co., 

18.0 

19.850 

Custer 

City,  Pa.     Two  determinations 

1(6) 

17.6 

26.616 

2.663 

*  These  samples  were  collected  by  Mr.  G.  B.  Richardson. 


490  DETERMINATION   OF   PORE   SPACE 

DISCUSSION 

R.  VAN  A.  MILLS,*  Washington,  D.  C. — Changes  induced  in  the  sands 
by  drilling  and  operating  wells  have  an  important  bearing  on  this  paper ; 
the  porosities  of  sands  and  the  sizes  of  grains  and  of  pores  change  as  the 
wells  produce.  Reductions  in  porosity  and  sizes  of  pores  are  caused  by 
induced  cementation,  brought  about  through  the  infiltration  of  reactive 
waters  into  the  wells  and  through  the  breaking  down  of  bicarbonates  in 
the  oil-field  waters  incident  to  the  liberation  of  carbon  dioxide  when 
wells  are  drilled  and  operated.  The  resistance  to  flow  increases  and 
the  rate  of  production  decreases  as  the  sizes  of  the  pores  are  reduced. 
Account  must  be  taken  of  these  facts  in  order  to  establish  valid  relations 
between  the  initial  rates  of  production  of  wells  and  the  porosities  of. 
sands  that  have  undergone  induced  cementation. 

The  textures  and  bedding  in  sandstones  are  extremely  variable  and 
it  is  doubtful  if  many  of  the  lumps  of  sand  collected  from  wells  after 
they  are  shot  are  truly  representative  of  the  pays.  In  many  sands,  the 
porous,  open-textured  parts  of  the  pays  are  so  soft  and  friable  as  to  be 
disintegrated  by  shooting,  so  that  most  of  the  remaining  lumps  represent 
hard,  tight  parts  of  the  sands.  The  collecting  of  representative  samples, 
together  with  adequate  collateral  data,  constitutes  an  important  part  of 
the  investigation  outlined  by  Mr.  Melcher. 

W.  M.  SMALL,  Tulsa,  Okla. — Has  Mr.  Mills  any  ideas  concerning  the 
zone  of  influence  within  which  this  cementation  would  take  place;  would 
it  be  more  pronounced  close  to  the  bore  hole  and  how  far  would  it  extend 
into  the  rock? 

R.  VAN  A.  MILLS. — That  is  a  difficult  question  to  answer  at  the 
present  stage  of  the  investigation.  The  greatest  deposition  of  carbonates 
occurs  within  or  close  to  the  wells,  but  in  some  fields  there  is  evidence 
that  the  sands  become  plugged  in  this  way  at  ^considerable  distances 
from  the  wells.  Shallow  pay  sands  are  frequently  calcareous  throughout 
considerable  areas,  but  this  may  be  caused  by  natural  agencies  similar  to 
those  causing  induced  cementation.  Some  new  wells  in  old  fields  reveal 
induced  cementation  by  carbonates  several  hundred  feet  from  the  nearest 
old  wells,  but  how  general  this  may  be  remains  to  be  determined.  Photo- 
graphs of  lumps  of  sand  shot  and  cleaned  from  old  wells  in  Butler  County, 
Pennsylvania,  were  published  in 'Geological  Survey  Bulletin  693.  These 
photographs  show  how  thoroughly  the  sands  were  plugged  by  carbonates. 

In  parts  of  Ohio  there  is  much  evidence  that  declines  in  production 
are  due  largely  to  induced  cementation  of  the  sands.  This  is  indicated 
not  only  by  the  examination  of  sands  from  the  old  wells,  but  by  the  high 

*  Petroleum  Technologist,  U.  S.  Bureau  of  Mines. 


DISCUSSION  491 

yields  of  new  wells  drilled  among  the  old  cemented  wells.  In  one  locality 
where  the  old  wells  have  declined  to  average  yields  of  approximately 
%  bbl.  per  day,  the  initial  rates  of  production  of  new  wells,  drilled  within 
300  ft.  of  the  old  wells,  run  as  high  as  50  bbl.  per  day.  In  many  cases, 
the  wells  in  this  field  were  abandoned,  not  because  the  oil  was  exhausted 
but  because  the  sands  became  so  cemented  that  the  oil  would  not  pass 
through.  The  Bureau  of  Mines  is  pursuing  field  and  laboratory  experi- 
ments upon  the  removal  of  carbonates  from  the  pay  sands  immediately 
around  old  oil  wells  through  the  use  of  chemical  reagents.  These 
experiments  afford  considerable  promise  of  successful  application. 

R.  VAN  A.  MILLS  (written  discussion*). — The  trend  of  modern 
petroleum  technology  is  to  displace  speculation  by  establishing  facts 
and  relationships  through  which  to  interpret  underground  conditions. 
Conditions  in  the  sands,  such  as  thickness  and  lenticularity,  coarse  or 
fine  textures,  openly  porous  or  tight  sands,  initial  or  induced  cementa- 
tion,14 initial  or  depleted  rock  pressures,  the  presence  or  absence  of 
water  are  mapped  as  guides  to  the  development  and  operation  of  fields. 
Samples  of  sand  from  apparently  barren  beds  penetrated  by  the  drill 
are  examined  to  determine  their  possible  productivity.  Underground 
conditions  that  change  during  the  operation  of  wells,  more  especially 
the  changes  in  the  textures  of  pay  sands  caused  by  induced  cementa- 
tion, and  the  movements  and  rearrangements  of  the  fluids,  such  as  the 
encroachment  of  water,  are  closely  observed  and  recorded  on  field  and 
office  maps.  More  reliable  criteria  for  the  valuation  of  oil  and  gas 
properties  are  being  established;  studies  of  the  probable  oil  and  gas 
content  of  sands,  together  with  the  production  records  of  wells,  are  being 
supplemented  by  studies  of  the  conditions  or  causes  governing  the  rates 
of  production.  In  all  of  this  work  and  in  the  operation  and  conservation 
of  individual  wells,  investigations  like  those  outlined  by  Mr.  Melcher 
are  of  primary  importance. 

The  United  States  Geological  Survey  Bulletin,15  from  which  Mr. 
Melcher  has  taken  his  Table  5,  production  data,  and  other  field  notes, 
establishes  the  importance  of  correlating  physical  and  chemical  studies 
of  the  reservoir  rocks  and  contained  fluids  with  the  production  histories 
of  the  wells  to  establish  relationships  for  practical  application,  but  the  few 
production  figures  published  are  not  adequate  for  the  use  Mr.  Melcher 

*  Published  by  permission  of  the  Director,  U.  S.  Bureau  of  Mines. 

14  The  term  induced  is  used  to  designate  the  deep-seated  effects  of  man's  activities. 
The  cementation  of  pay  sands  incident  to  the  drilling  and  operation  of  wells  is  one  of 
the  induced  effects  in  oil  and  gas  fields  previously  described  by  the  writer.  See  U.  S. 
Geol.  Survey  Butt.  693,  44-55,  and  98. 

16R.  V.  A.  Mills  and  R.  C.  Wells:  Evaporation  and  Concentration  of 
Associated  with  Petroleum  and  Natural  Gas.    U.  S.  Geol.  Survey  Bull.  693 


492 


DETERMINATION   OF  PORE   SPACE 


makes  of  them.  They  suggest  broad  relationships  that  the  porosities  and 
sizes  of  pores  bear  to  the  initial  rates  of  production  from  a  few  wells,  but 
these  relationships  might  be  more  definitely  established,  in  the  Appala- 
chian fields,  by  using  the  large  collection  of  sands  and  accompanying 
field  notes  and  production  data  that  the  writer  and  others  have  contri- 
buted to  the  Geological  Survey. 


FIG.  4. — APPARATUS  FOB  STUDYING  CAUSES  AND  EFFECTS  OP  MIGRATION  OF  OIL  AND 
WATER  THROUGH  OIL  SAND.    (Plate  XXII,  U.  S.  Bureau  of  Mines  Butt.  175.) 

In  studying  subsurface  relationships,  we  are  obliged  to  deal  with  the 
summations  of  effects  of  many  factors  whose  values  are  only  relative  and 
rarely  alike  in  different  localities  or  at  different  depths  in  the  same  lo- 
cality. Porosity  and  size  of  pores  are  among  these  factors.  A  minimum 
porosity  value,  or  a  minimum  size  of  pores,  below  which  sands  are  non- 
productive in  one  locality,  need  not  necessarily  apply  in  localities  where 


DISCUSSION  493 

the  bedding  of  the  sands,  the  modes  of  occurrence  of  oil,  gas,  and  water, 
the  viscosities  of  the  oils,  the  gas  pressures,  the  subsurface  temperatures, 
etc.  are  different.  Consequently,  it  is  imperative  that  various  principles 
and  relationships  be  studied,  in  conjunction  with  porosity  tests,  through 
adequate  field  and  laboratory  methods  for  each  locality. 

The  writer  supplements  field  work  and  porosity  tests,  such  as  Mr. 
Melcher  describes,  by  comparative  studies  of  fluid  movements  through 
sands  arranged  in  steel  tanks.  The  tanks  are  equipped  with  plate-glass 
fronts,  to  facilitate  observations  and  the  making  of  photographic  records 
of  experiments.  Oils  from  different  fields  are  used,  the  number  of  vari- 
ables in  each  experiment  is  restricted,  and  the  relative  values  of  different 
factors  such  as  porosity,  viscosities  of  oils,  buoyancies  of  oils  and  gases  in 
water-saturated  sands,  expansive  forces  of  compressed  gases  in  sands, 
capillary  forces,  and  many  other  factors  are  definitely  established  for  each 
set  of  experimental  conditions. 

The  importance  of  adequate  field  methods  and  notes  in  the  collection 
of  samples  of  oil-  and  gas-bearing  sands  must  also  be  emphasized.  It 
should  be  understood  that  a  large  proportion  of  the  hard,  densely  cement- 
ed fragments  shot  and  cleaned  from  wells  represent  so-called  shells, 
breaks,  and  tight  sand,  rather  than  true  pay  sands.  Many  of  the  pay 
sands  are  so  granular  and  friable  as  to  render  lump  samples  exceptional, 
but  where  lump  samples  of  the  "pays"  can  be  obtained,  they  should  be 
collected  before  they  have  been  exposed  to  the  weather.  It  is  good  prac- 
tice to  collect  several  lumps  together  with  loose  sand  from  the  same  well 
for  comparison.  Large  proportions  of  the  loose  sands  cleaned  from  shot 
cavities  in  producing  wells  come  from  the  relatively  friable  pays.  The 
textures  of  these  loose  sands  furnish  criteria  for  the  identification  of 
lumps  from  the  same  parts  of  the  beds.  Care  should  be  taken  to  differ- 
entiate between  loose  sands  from  shot  cavities  and  drill  sludge,  which  is 
unsatisfactory  because  of  its  pulverized  condition. 

Owing  to  the  extremely  variable  nature  of  beds  of  sandstone,  no  part 
or  section  of  a  sandstone  may  be  regarded  as  truly  representative  of  the 
bed.  But  the  average  result  of  several  porosity  tests  upon  a  carefully 
selected  multiple  sample  from  the  productive  horizon  in  a  well  should 
most  nearly  represent  the  porosity  of  the  pay  sand  at  that  place.  Ade- 
quate studies  of  the  variations  in  texture  and  porosity  of  pay  sands,  and 
the  relationships  that  these  conditions  bear  to  the  occurrence  and  re- 
covery of  oil  and  gas  can  be  made  only  through  intensive  field  and  labora- 
tory work.  Samples  of  the  sands  should  be  collected  in  conjunction  with 
detailed  geologic  studies  of  a  field  or  by  a  resident  engineer  or  geologist 
during  the  development  and  operation  of  the  field.  But  no  matter  how 
the  work  is  done  samples  of  the  pay  sands,  drill  logs,  and  production 
records  from  as  many  wells  as  possible  should  be  obtained  and  applied 
in  each  field  under  examination. 


494  DETERMINATION   OF   PORE   SPACE 

To  establish  the  relationships  that  porosity  and  size  of  pores  in  sands 
bear  to  productivity,  it  is  advantageous  to  collect  samples  of  the  non- 
productive rocks  for  comparison  with  pay  sands.  Pieces  of  non-produc- 
tive rocks  are  occasionally  brought  to  the  surface  through  the  shooting 
of  dry  holes;  also  pieces  of  the  cap  sands  are  sometimes  ejected  in  shooting 
the  pays,  but  for  the  most  part  we  must  depend  for  these  samples  on 
small  fragments  or  chips,  of  uncertain  origin,  found  in  the  drill  sludge  and 
cavings  cleaned  out  while  the  wells  are  being  drilled.  The  use  of  core 
drills  for  sampling  oil  sands  and  their  associated  rocks  has  long  been  con- 
sidered, but  the  writer  believes  that  a  sampling  device  (working  on  the 
same  principle  as  the  under  reamer)  that  will  break  fragments  from  the 
walls  of  a  well  as  it  is  being  drilled  should  prove  advantageous  to  compan- 
ies applying  physical  and  chemical  studies  of  oil-  and  gas-bearing  rocks. 

The  period  in  the  productive  history  of  a  well  at  which  a  sample  of  pay 
sand  is  collected,  together  with  the  water  conditions  in  the  well,  have 
much  to  do  with  the  physical  and  chemical  qualities  of  the  rock  and  the 
relationships  that  these  qualtites  bear  to  production.  The  porosities, 
sizes  of  pores,  and  chemical  compositions  of  water-bearing  pay  sands  fre- 
quently undergo  marked  changes  during  the  operation  of  wells.  The 
induced  cementation  of  pay  sands  by  carbonates  is  exceedingly  common 

Through  the  cooperation  of  Mr.  C.  W.  Paine,  of  Ozark,  Mr.  George 
Vandergrift,  of  Woodsfield,  and  other  operators  in  that  locality,  the 
writer  has  had  the  groups  of  Ohio  wells,  cited  by  Mr.  Melcher,  under  sur- 
veillance since  the  summer  of  1914.  The  subsurface  geology  has  been 
studied  in  detail16  and  samples  of  the  oils,  gases,  waters,  and  reservoir 
rocks  have  been  collected  and  examined  periodically.  Some  of  these 
wells  have  now  (April,  1920)  ceased  to  produce  because  the  pay  sands  are 
plugged  by  inorganic  deposits  from  the  waters  associated  with  the  oil. 
The  porosities  and  sizes  of  pores  in  the  pay  sands  around  the  wells  have 
been  so  reduced  as  to  stop  production.17  New  wells  situated  within  300 
ft.  of  the  old  ones,  and  drilled  after  the  old  wells  had  been  abandoned, 
yielded  oil  at  initial  rates  as  high  as  10  bbl.  per  day  from  the  same  sands; 
apparently  from  the  same  pays,  where  they  had  not  been  plugged. 

The  causes  and  effects  of  induced  cementation  have  already  been  de- 
scribed.18 To  ignore  them  in  studying  the  relationships  that  porosity  and 
sizes  of  pores  bear  to  the  productivity  of  sands  may  cause  errors.  For 
instance,  consider  two  of  the  sands  represented  in  Table  1,  which  together 
with  the  other  Ohio  sands  cited  by  Mr.  Melcher,  were  collected  and  ex- 
amined in  the  preparation  of  Geological  Survey  Bulletin  693.  The  Berea 

16  R.  Van  A.  Mills  and  D.  Dale  Condit:  Unpublished  manuscript  and  maps  in  the 
files  of  the  United  States  Geological  Survey. 

17  Figures  showing  changes  in  composition  and  reductions  in  porosity  and  sizes 
of  pores  will  be  presented  in  later  papers. 

"  See  U.  S.  Geol.  Survey  Butt.  693,  44-50  and  98. 


DISCUSSION 


495 


sand,  from  Armstrong's  Mills,  was  collected  from  an  oil  and  gas  well  that 
had  been  producing  for  ten  years.  The  initial  rate  of  production  from  the 
well  was  100  bbl.  of  oil  per  day,  but  in  1914,  when  the  sample  was  collected, 
the  rate  of  production  had  declined  to  about  2  bbl.  of  oil  with  a  little  water. 
Chemical  and  petrographic  examinations  of  the  sand  indicate  that  it 
has  undergone  induced  cementation  through  the  deposition  of  carbonates. 
Judging  from  the  high  proportion  of  secondary  carbonates  in  the  sample 
the  original  porosity  may  have  been  diminished  7.7  per  cent,  of  the  volume 
of  the  rock.19  The  sizes  of  pores  and  the  permeability  of  the  sand  have 
undoubtedly  been  diminished  since  the  well  started  to  produce.  Conse- 
quently the  porosity  and  sizes  of  pores  in  this  sample  can  bear  no  valid 
relation  to  the  initial  rate  of  production  of  the  well.  To  interpret  the 
loss  by  ignition  of  this  sample  as  a  loss  of  combustible  matter  is  erroneous. 
As  shown  in  the  accompanying  table,  the  sample  contains  4.23  per  cent., 
by  weight,  of  C02  combined  with  calcium,  magnesium,  and  iron  to  form 
carbonates.  Part  of  this  C02  would  probably  be  lost  during  ignition 
of  the  oil  and  paraffin  contained  in  the  sample.  If  the  hydrocarbons  in 
this  sample  were  removed  by  ignition  prior  to  the  porosity  measurements, 
the  value  of  the  porosity  measurements  themselves  were  impaired  through 
the  breaking  down  of  the  carbonate  minerals,  which  constituted  an  im- 
portant part  of  the  sample. 

TABLE  12. — Analyses  of  Sands  from  Oil  Wells* 
(R.  C.  Wells,  Analyst) 


Keener  Sand  from  Well 
No.  2,  J.  R.  Scott  Farm 
Per  Cent. 

Berea  Sand  from  Well 
on  Shepherd  Farm, 
Per  Cent. 

SiO2  

93.82 

85.90 

Fe2O3  (all  Fe  as  FezOs) 

1  75 

2  82 

A12O8                              

0.73 

1  68 

CaO 

0  19 

2  96 

MgO 

0.25 

0.84 

P2O                                            

0  02 

0  03 

CO2 

Trace 

4  23 

TiO3                  

0.12 

0  12 

Loss  on  ignition  less  COj 

2  31 

1  35 

99.19 


99.93 


*  U.  S.  Geol.  Survey  Bull.  693,  17. 


19  The  calculation  is  based  on  the  assumption  that  the  sample,  having  a  total 
porosity  of  16.8  per  cent.,  contained  4.23  per  cent,  by  weight  of  COa  combined  with 
calcium,  magnesium,  and  iron  to  form  carbonates,  and  also  that  the  sand  was  free  from 
carbonates  when  the  well  was  drilled.  The  examination  of  a  large  number  of  samples 
of  water-bearing  pay  sands  from  new  wells  in  new  fields  in  Ohio,  Pennsylvania,  and 
West  Virginia  reveals  only  traces  of  carbonates. 


496  DETERMINATION   OP   PORE   SPACE 

The  [Keener  sand  from  well  No.  2  on  the  J.  R.  Scott  farm,  near 
Jerusalem,  Ohio,  though  collected  after  the  well  had  been  producing  for  1 1 
years,  apparently  had  not  undergone  induced  cementation.  The  sand 
contained  only  a  trace  of  C02  and  the  well  has  remained  the  best  pro- 
ducer in  the  field.20  The  injury  to  the  sand  that  necessitated  shooting  the 
well  was  caused  by  so-called  paraffining  of  the  sand,  and  the  high  per- 
centage of  combustible  matter  in  the  sample  was  due  to  the  presence  of 
waxy  hydrocarbons,  which  reduced  the  effective  porosity.  The  examina- 
tion of  this  sample,  after  the  hydrocarbons  were  burned  off,  furnishes 
more  reliable  data  for  use  in  establishing  the  relationships  that  porosity 
and  sizes  of  pores  bear  to  initial  rates  of  production. 

The  relationships  that  total  porosities  of  coherent  sands  may  bear  to 
the  rates  of  production,  as  well  as  to  the  ultimate  productions  from  such 
sands,  depend  largely  on  relationships  between  total  porosities,  effective 
porosities,  and  sizes  of  pores.  All  of  these  conditions  are  related  one  to 
the  other  and  all  of  them  influence  the  retentivity  as  well  as  the  fluid 
movements  through  sands.  Cementation,  either  natural  or  induced,  has 
played  a  major  role  in  reducing  the  total  and  effective  porosities  of  lithi- 
fied  sands,  but  it  has  likewise  reduced  the  sizes  of  the  pores.  The  most 
densely  cemented,  or  in  other  words  the  least  porous,  of  the  lithified  sedi- 
ments generally  contain  relatively  fine  pores.  In  unconsolidated  sands, 
where  there  has  been  little  cementation,  the  total  porosities,  effective 
porosities,  and  sizes  of  pores  are  not  so  closely  related.  The  writer's 
experiments  with  unconsolidated  sands  indicate  that  sizes  of  pores,  and 
especially  the  sharp  variations  in  the  sizes  of  pores  between  different  beds 
or  in  different  parts  of  the  same  beds,  are  factors  of  primary  importance  in 
the  movements  of  oil  and  gas  through  water-bearing  strata,  regardless  of 
total  porosities.21 

The  selective  or  differential  permeabilities  of  sands  to  waters,  oils 
and  gases  are  also  of  primary  importance  in  recovery  problems.  These 
selective  or  differential  permeabilities  depend  not  only  on  the  porosities 
and  sizes  of  pores  of  the  sands,  and  the  viscosities,  pressures,  and  tem- 
peratures of  the  fluids,  but  also  on  the  order  and  degree  with  which  the 
sands  have  become  wet  or  saturated  by  water  or  .oil.  Studies  of  these  re- 
lationships, especially  the  studies  of  effective  porosity  and  of  permeability 
that  Mr.  Melcher  proposes  to  make,  constitute  a  new  and  promising  phase 
of  petroleum  technology  in  which  real  advances  can  be  made  only  through 
intensive  field  work  supplemented  by  systematic  and  scientific  laboratory 
experimentation. 

20  See  U.  S.  Geol.  Survey  Bull  693,  97. 

21  R.  Van  A.  Mills:  Experimental  Studies  of  Subsurface  Relationships  in  Oil  and 
Gas  Fields.     Manuscript  in  course  of  publication. 


DISCUSSION  497 

C.  W.  WASHBURNE,  New  York,  N.  Y.  (written  discussion). — This 
paper  marks  an  advance  in  technical  methods.  The  data  indicate  that 
the  oil-bearing  parts  of-  sands  are  not  more  porous  than  the  same  sands  at 
their  outcrops,  a  result  that  does  not  accord  with  the  prevailing  opinion 
of  many  geologists,  none  of  whom,  however,  has  made  such  extensive 
observations.  The  figures,  though,  should  be  regarded  as  minima  rather 
than  averages,  for  the  observations  were  made  on  coherent  chunks  of  oil 
sand  obtained,  probably,  from  the  bottom  of  drill  holes  without  the  use  of 
core  barrels.  Chunks  of  this  kind  probably  represent  the  harder,  more 
cemented,  and  less  porous  parts  of  the  sand.  The  greater  part  of  the 
sand  is  more  friable;  it  is  ground  up  by  the  bit  and  comes  out  as  sand,  not 
as  fragments  of  stone.  Chunks  obtained  from  wells,  therefore,  are  not 
likely  to  be  average  samples  of  the  sand. 

To  get  the  true  average  porosity  of  a  sand,  cores  of  the  whole  sand 
should  be  obtained.  The  cores  obtained  by  the  core  barrel  on  the  Gulf 
Coast  are  too  fragile  to  ship,  except  in  the  core  barrel  itself.  The  efficient 
field  manager  must  study  these  cores  before  deciding  how  to  case  and  tube 
his  well.  He  must  therefore  break  them  up  immediately  at  the  well.  It 
would  give  a  truer  figure  of  porosity  if  a  method  were  developed  whereby 
the  porosity  of  these  cores  could  be  determined  in  the  field  without  inter- 
fering with  the  driller 's  examination. 


VOL.  LXV. — 32. 


498  WATER   DISPLACEMENT   IN   OIL   AND    GAS   SANDS 


Water  Displacement  in  Oil  and  Gas  Sands 

BY  ROSWELL  H.  JOHNSON,  M.  S.,  PITTSBURGH,  PA. 

(New  York  Meeting,  February,  1920) 

ALL  STRATA  not  yielding  oil  or  gas  in  commercial  quantities  or  a  cor- 
responding amount  of  water  may  be  called  dry  in  a  wide  sense.  In 
petroleum  geology,  however,  we  may  exclude  all  sands  of  too  low  or  fine 
porosity  to  yield  gaseous  or  fluid  contents  to  the  hole  drilled  in  the  sand 
before  any  original  pressure  that  its  contents  may  be  under  is  disturbed. 
Most  rocks  are  of  this  class  and  they  are  not  reservoirs  in  our  definition; 
their  "dryness"  is  wholly  a  matter  of  course.  What  are  the  contents 
of  the  pores  or  what  is  the  exact  porosity  of  such  rocks  is  of  almost  no 
concern  to  us,  for  economically  they  are  "dry." 

What  does  interest  us  is  the  content  of  a  rock  having  sufficient  poros- 
ity and  the  pores  of  sufficient  size  to  yield  oil  or  gas  in  commercial  quan- 
tities, if  they  were  present  under  original  pressure.  Dryness  of  these 
reservoirs  is  a  matter  of  supreme  practical  importance.  Three  views 
current  as  to  such  dryness  seem,  to  me,  to  apply  in  a  few  cases  only.  It 
is  the  purpose  of  this  paper  to  give  reasons  for  this  position  and  for  be- 
lieving that,  in  ordinary  sedimentary  rocks,  there  is  only  rarely  a  reser- 
voir of  competent  porosity  and  undisturbed  pressure  that  is  dry  in  the 
sense  of  not  yielding  water,  oil,  or  gas  when  first  penetrated. 

1.  Gardner1  writes  of  some  Kentucky  sands,  "There  has  never  been 
present  any  salt  water  or  other  water  in  the  sand."    Absence  of  water 
cannot  demonstrate  this  position.     It  is  necessary  to  show  that  the  rocks 
were  not  laid  down  in  water,  but  in  air,  and  that  they  became  so  enclosed, 
while  still  above  the  water-table  of  the  ground  water,  that  water  has  not 
been  able  to  enter  since.     Most  of  these  sands,  and  certainly  the  pro- 
ductive limestones,  were  deposited  in  water;  and  such  sands  as  have  been 
commercially  productive  show  no  reason  for  believing  that  the  overlying 
shale  or  limestone  was  not  laid  down  progressively  from  one  direction 
and  in  water  that  would  have  flooded  it.     No  adequate  explanation  has 
been  offered  for  this  hypothesis,  which  is  so  inherently  improbable. 

2.  Reeves2  urges  that  "sands  originally  water  filled  may  have  been 
drained  of  their  water  and  not  filled  when  later  covered."     It  is  difficult 

i  James  H.  Gardner:  Kentucky  as  an  Oil  State.    Science,  N.  S.  (1917)  46,  279-280. 

*F.  Reeves:  Origin  of  the  Natural  Brines  of  Oil  Fields.  Johns  Hopkins  Univ. 
Circ.,  N.  S.  (1917)  N.  3; 

Absence  of  Water  in  Certain  Sandstones  of  the  Appalachian  Field.  Econ.  Geol. 
(1917)  12,  354-378. 


ROSWELL  H.   JOHNSON  499 

to  see  how  the  presence  of  the  air  could  prevent  the  entrance  of  water 
where  the  water  overlaps  the  sand  from  one  side  and  so  has  ample  op- 
portunity to  expel  the  air.  However,  we  have  an  excellent  test  of  whether 
the  sand  is  dry  because  air  filled,  as  supposed  by  Gardner,  by  merely  ana- 
lyzing this  supposed  entrapped  air.  Instead  of  the  air  called  for  by 
Reeves'  hypothesis  we  nearly  always  find  methane.  There  are  very  rare 
occasions  where  it  is  mainly  nitrogen,  probably  entrapped  air  denuded 
of  its  oxygen  by  the  oxidizing  of  materials  in  contact.  For  these  occa- 
sions, as  at  Dexter,  Reeves'  hypothesis  is  helpful;  but  its  unimportance 
is  measured  by  the  extreme  rarity  of  such  cases. 

3.  Shaw  holds  that  a  sand  may  be  adequately  porous  and  hold  water 
and  yet  not  yield  it  to  a  drill  hole  because  of  lack  of  expansive  force 
behind  it.  In  view  of  the  almost  universal  rule  of  an  increase  of  pressure 
with  depth  in  our  ordinary  sedimentary  strata,  such  as  we  find  in  oil 
fields,  such  a  failure  must  be  excessively  rare. 

An  absence  of  methane  would  not  be  expected  in  the  sedimentary 
series  in  which  our  oil  and  gas  fields  are  found,  because  these  rocks  are 
so  generally  charged  with  some  gas,  either  free  or  dissolved  in  oil,  in 
some  part  of  the  reservoir.  Even  with  no  methane,  we  know  that  pro- 
pane and  butane  are  soluble  in  water  to  an  extent  of  nearly  3  per  cent, 
so  that  they  could  give  it  expansibility  for  at  least  a  short  time. 

DISPLACEMENT  AND  RESULTING  MOVEMENT  IN  OIL  AND  GAS  SANDS 
Concluding,  then,  that  the  reservoirs  now  containing  oil  and  gas 
originally  were  water  filled  and  that  the  gas  and  oil  later  entered  the 
reservoir,  thereby  displacing  water,  it  becomes  a  matter  of  interest  to 
postulate  the  resulting  movement  of  the  oil,  gas,  and  water,  respectively. 
We  may  assume  that  the  oil  and  gas  enter  on  all  sides  of  the  reservoir. 
If  at  the  bottom  they  would  rise  to  the  top,  although  in  all  probability 
generally  deflected  en  route  along  some  bedding  plane.  Having  reached 
the  roof  of  the  reservoir,  since  this  is  ordinarily  elongated  and  pitching, 
they  would  move  along  the  inclined  plane  until  they  formed  an  oil  and 
gas  accumulation  at  the  upper  end. 

The  matter  of  especial  interest  to  us  is  the  action  as  it  finds  minor 
dome-like  irregularities.  These  will  necessarily  be  filled  if  there  is  enough 
oil  and  gas  to  fill  them.  If  more  than  enough  oil  and  gas  reach  these 
local  catchments,  the  oil  and  gas  will  resume  their  movement  up  dip. 
However,  as  this  movement  continues,  the  proportion  of  the  gas  in 
these  catchments  will  increase.  Indeed,  the  oil  may  nearly  all  be  forced 
down  into  the  general  stream  and  so  move  on  up  to  the  highest  oil  and 
gas  mass.  In  this  motion  upward  along  the  crest  of  the  reservoir,  the 
path  would  not  be  a  broad  one.  Any  " bulge"  in  the  roof  to  one  side 
of  such  a  "path"  would  not  be  fed  with  oil  and  gas,  except  such  as 
was  caught  by  direct  upward  movement  to  it  by  side  paths  flowing 


500  WATER   DISPLACEMENT   IN   OIL   AND    GAS   SANDS 

on  the  way  to  the  ridge.  If  the  crest  of  the  reservoir  was  very  flat  and 
broad,  we  might  possibly  have  a  series  of  braided  paths,  such  as  one 
finds  in  some  rivers  of  broad  bed.  In  the  top  mass  of  oil  and  gas  to 
which  the  paths  lead,  the  percentage  of  oil  to  gas  should  be  higher  than 
any  bulge  below  because  of  the  excessive  proportion  of  gas  held  below. 
This  selective  action  explains  some  of  the  differences  in  relative  per- 
centage of  gas  and  oil  in  different  pools.  Suppose  now  the  reservoir  as 
a  whole  is  arched,  each  flank  is  then  working  as  before  suggested  but 
the  oil-gas  mass  is  held  at  the  crest  instead  of  by  the  termination  of 
the  reservoir. 

So  far  as  the  upward  motion  of  the  oil -and  gas  has  been  discussed,  we 
have  assumed  that  there  are  no  obstacles  to  the  free  motion  of  any  mole- 
cule of  oil  and  gas,  as  directed  by  gravitation.  However,  one  serious 
obstacle,  surface  tension,  leads  to  the  oil  or  gas  rounding  off  into  a  bubble, 
which  thereby  offers  great  resistance  to  motion  in  sandstone  as  fine  as  we 
generally  find  it.  A  bubble  forms  in  each  "chink"  between  grains,  but 
its  oil  cannot  move  until  the  bubble  grows  so  large  as  to  extend  as  a 
bud  through  one  of  the  larger  passageways  into  the  adjoining  chink 
between  grains.  Only  a  continuous  invasion  can  make  progress.  It  is 
a  mistake  to  think  of  a  passage  of  a  series  of  bubbles  as  such.  The 
resistance  in  that  case  would  be  so  great  that  gravitation  at  least  would 
be  impotent  except  with  very  coarse  deposits. 

The  water  must  have  a  motion  away  from  the  upper  part  of  the  reser- 
voir as  the  movement  of  the  oil  and  gas  upward  along  the  roof  drives  the 
water,  in  part,  back  into  the  shale  and,  in  part,  down  the  reservoir  to  the 
lower  end.  Again,  we  must  consider  the  effect  of  depressions  in  the  floor 
(whether  depositional  or  deformational)  on  the  water  as  it  recedes  to  the 
lower  end  of  the  reservoirs.  The  water  would  fill  each  depression  and  spill 
over  its  oil  in  the  general  movement  down  the  reservoir.  It  retains  a 
disproportionate  share  of  water  after  all  the  oil  and  water  have  passed 
this  depression  going  down  dip.  Some  of  the  water  may  be  forced  out 
through  the  floor  of  the  reservoir,  but  it  would  usually  leave  the  water 
in  excess  until  the  gas  accumulation  was  quite  large.  Therefore  we 
conclude  that  these  depressions  are  less  favorable  points  for  oil  and 
that  most  of  the  oil  will  accumulate  at  the  lowest  part  of  the  reservoir, 
assuming  that  the  displacement  continues  that  long.  The  lowest  part 
of  the  reservoir  being  so  frequently  a  matter  of  lateral  variation  or 
" tailing"  of  the  bed,  this  place  is  more  difficult  to  locate.  Hence  the 
search  for  oil  in  sands  without  water  is  more  difficult  than  in  those 
carrying  much  water.  It  is  not  a  case  of  mere  reversal,  seeking  anti- 
clines in  one  case  and  synclines  in  the  other.  Structure  is,  then,  of  still 
less  help  in  the  waterless  sands  than  would  otherwise  be  supposed. 


DISCUSSION  501 

DISCUSSION 

DAVID  WHITE,*  Washington,  D.  C. — This  is  a  most  interesting  point 
concerning  the  genesis  and  distribution  of  oil,  gas,  and  water  in  rocks. 
According  to  common  acceptance,  a  dry  sand  is  one  from  which  oil,  water 
or  gas  will  not  exude  when  it  is  penetrated  by  the  drill  or  the  mine  shaft. 
However,  strictly  speaking,  there  is  no  arenaceous  sediment  or  clastic, 
not  excepting  eoKan  sands,  which  has  not  been  laid  down  in  water  or  has 
not  later  been  submerged  beneath  and  filled  with  water  before  any  sealing 
cap-rock  has  been  laid  down.  All  sands  have  at  some  time  been  full  of 
water.  .  The  expulsion  of  the  water  under  varying  conditions  is  a  topic 
not  yet  adequately  discussed.  It  does  not  seem  to  have  been  generally 
recognized  that  the  essential  reason  why  oil  does  not  flow  from  the  sand 
when  resistance  is  removed  by  perforation  by  the  drill  or  the  mine  shaft 
probably  lies  in  the  fact  that  former  pressures  have  been  reduced  to  the 
point  where  capillary  resistance  prevents  the  outflow  into  the  void. 
There  is  one  more  question :  Does  the  deformation  occur  while  the  oil, 
gas,  and  water  are  in  process  of  migration,  or  do  these  migrate  after  the 
deformation  occurs?  Deformation  takes  a  long  time.  The  migration 
also  ought  to  require  a  long  period.  Is  not  the  migration  in  progress 
when  the  deformation  is  developed? 

G.  H.  ASHLEY,  Harrisburg,  Pa. — Within  the  past  few  months  there 
has  been,  in  the  McKeesport  gas  pool  in  western  Pennsylvania,  a  develop- 
ment that,  if  it  has  been  properly  interpreted,  has  some  bearing  on  this 
problem.  The  principal  gas  reservoir  is  the  so-called  Speechley  sand, 
found  at  a  depth  of  about  2900  ft.  (884  m.).  Between  400  and  500  ft. 
above  that  is  the  Elizabeth  sand.  The  first  big  well  contained  too 
much  gas  to  be  carried  off  by  the  6-in.  main  that  had  been  laid,  so  a  valve 
was  placed  in  the  main  to  allow  the  escape  of  gas  above  a  pressure  of 
430  Ib.  Mr.  Tonkins,  of  the  Peoples  Gas  Co.,  suggests  that  as  a  result 
of  the  back  pressure  thus  generated  in  that  big  well  the  gas  from  the 
lower  sand  entered  the  upper,  or  Elizabeth,  sand  and  enriched  it,  as 
indicated  by  the  fact  that  other  wells  put  down  to  the  upper  sand  have 
increased  their  flow  and  later  wells  have  obtained  an  enlarged  flow  from 
that  upper  sand.  If  that  is  true,  it  indicates  that  the  Elizabeth  sand 
was  dry,  not  because  nothing  would  flow  out  of  it  or  into  it,  nor  because 
of  closeness  of  grain,  for  otherwise  the  sand  would  not  have  taken  up  gas. 

SIDNEY  PAIGE,  f  Washington,  D.  C. — You  say  the  back  pressure; 
could  the  back  pressure  have  been  any  greater  than  the  original  pressure 
before  the  oil  was  tapped?  How  would  this  new  movement  have 
occurred?  It  is  not  clear  to  me. 

*  Chief  Geologist,  U.  S.  Geol.  Survey, 
t  Geologist,  U.  S.  Geol.  Survey. 


502  WATER   DISPLACEMENT  IN   OIL   AND   GAS   SANDS 

G.  H.  ASHLEY. — Before  the  tapping  of  the  lower  sand,  there  was  no 
connection  between  the  upper  and  lower  sands. 

SIDNEY  PAIGE. — It  came  up  along  the  pipe? 

G.  H.  ASHLEY. — It  came  up  along  the  pipe;  there  was  no  tubing  or 
piping  between  the  sands.  The  100-ft.  sand  was  the  last  one  that  was 
cut  off. 

R.  H.  JOHNSON. — I  should  say  that  hydrocarbons  are  still  coming  in 
while  deformation  is  going  on.  The  main  reason  for  that  is  that  the 
deformation  is  particularly  active  in  making  hydrocarbons,  as  David 
White's  work  has  well  shown.  Most  of  the  hydrocarbons  must  come  into 
the  reservoirs  quite  a  little  later  than  was  formerly  thought. 

May  I  add  a  point  in  connection  with  this  well  at  McKeesport? 
At  the  Elk  City  gas  field,  the  other  prominent  gas  field  we  have  had 
recently,  the  pressure  started  to  decline  at  a  rather  rapid  rate,  but  when 
the  pressure  reached  a  certain  point,  the  decline,  although  we  were  taking 
out  still  more  gas,  was  not  so  rapid.  In  explanation,  it  was  said  that  the 
well  was  tubed  to  a  place  above  the  productive  sands,  so  that  there  was 
an  open  hole  of  several  feet.  This  sand,  when  first  struck,  I  would  suggest 
therefore  was  feeding  in  there  just  as  the  Elizabeth  was  being  fed  at  Mc- 
Keesport, so  the  pressure  dropped  fairly  rapidly  during  this  period  of 
underground  wastage;  but  after  this  sand  had  been  fed  to  its  capacity, 
apparently  the  pressure  declined  more  slowly.  I  suspect  that  something 
very  similar  happened  at  McKeesport. 

If  we  could  have  had  pressures  on  that  well  right  along,  we  could  have 
learned  something  about  the  feeding  situation.  The  Elizabeth  sand  was 
fed  until  it  would  take  no  more.  From  then  on,  of  course,  it  was  not  as 
serious  a  source  of  underground  wastage  except  as  the  gas  might  go  through 
other  wells  than  those  of  the  owner. 

These  Elizabeth  sands  are  not  as  large  as  they  really  ought  to  be, 
considering  the  magnificent  chance  of  being  charged  by  this  gigantic  well, 
which  seems  to  be  the  result  of  a  lower  porosity.  The  sands  yielded  a 
small  amount  of  gas  before  this  feeding  process  and  the  amount  since  is 
only  moderate  compared  with  the  great  wells;  I  should  say  that  was  be- 
cause it  did  not  have  the  capacity  to  receive  much  of  that  gas. 

E.  W.  SHAW,*  Washington,  D.  C. — In  the  Caddo,  Elm  Grove,  and 
Monroe  fields,  Louisiana,  we  have  such  extensive  underground  migration 
of  gas  that  after  some  of  the  big  wells  have  been  completed  but  not 
successfully  cased  the  country  all  around  sizzles.  The  gas  creeps  from 
one  sand  to  another  and  sometimes  blows  out  the  surface  as  much  as 
}/±  mile  from  the  well  where  it  left  its  natural  reservoir. 

*  Geologist,  U.  S.  Geol.  Survey. 


DISCUSSION  503 

I  do  not  see  the  bearing  of  this  on  the  question  of  dry  sands,  concern- 
ing which  there  seems  to  be  a  good  deal  of  difference  of  opinion,  for  the 
reason  that  when  the  gas  rises  from  a  lower  sand,  where  the  pressure  is 
high,  to  a  higher  sand,  where  the  pressure  is  low,  it  is  not  essential,  and 
it  is  not  to  be  inferred  that  the  pores  in  the  higher  sand  are  empty  or 
even  free  from  liquid  contents.  All  that  is  required  is  that  the  gas  or 
liquid  move  off  somewhere  else  or  accommodate  itself  in  smaller 
quarters. 

I  was  much  interested  in  Mr.  White's  remark  that  we  are  all  agreed 
that  pores  are  filled  with  something.  If  we  can  agree  on  this  we  have 
made  a  real  step  in  advance.  The  following  step  to  be  taken  is  longer 
and  more  difficult,  but  it  is  a  step  that  we  must  take  sooner  or  later. 
This  step  is  to  recognize  that  most  dry  sands  are  myths. 

R.  H.  JOHNSON. — The  question  of  the  helium  in  the  Kansas  and  some 
of  the  Texas  gases,  I  think,  has  a  bearing  on  Reeves'  hypothesis  of  en- 
trapped air.  Those  gases  have  more  helium  in  proportion  to  nitrogen 
than  the  air. 

In  this  paper,  I  have  accepted  the  notion  that  we  might  have  entrap- 
ped air  to  explain  these  nitrogen  reservoirs.  Since  writing  that,  I  have 
become  more  skeptical.  We  can  easily  explain  away  the  lack  of  oxygen; 
that  can  be  taken  up  to  make  carbonate,  but  why  this  super-atmospheric 
amount  of  helium?  These  helium  gases  may  have  a  deep-seated  origin 
over  faults  that  do  not  come  to  the  surface.  May  they  not  be  gases  of  a 
cosmic  nature — gases  that  have  been  extruded  from  original  earth  stuff 
from  still  greater  depths,  that  have  worked  along  some  faults  and  have 
not  been  able  to  get  closer  to  the  surface? 

Do  not  think  that  that  means  I  am  inclining  toward  any  inorganic 
origin  of  hydrocarbons,  but  if  we  do  not  accept  that  hypothesis,  we  have 
difficulty  in  getting  that  much  helium  because  the  air  rnust  have  been 
entrapped,  and  it  is  utterly  unreasonable  to  suppose  there  was  more 
helium  in  the  air  then  than  there  is  now.  I  dare  say  that  higher  up  in 
the  air,  there  is  a  greater  amount  of  helium,  but  that  will  not  help  us 
because  these  gases  were  laid  down  close  to  the  earth's  surface,  and  the 
gravitational  contrast  was  as  great  then  as  it  is  now. 

H.  W.  HIXON,  New  York,  N.  Y. — That  question  of  helium  in  the 
gases  goes  back,  I  believe,  to  the  origin  of  the  hydrocarbons;  and  while 
Mr.  Johnson  evidently  does  not  believe  in  the  inorganic  origin  of  oil  and 
natural  gas,  I  most  decidedly  do.  If  you  assume  that  the  earth  had  an 
origin,  it  must  have  been  either  according  to  the  planetesimal  hypothesis 
or  a  gaseo-molten  condition.  Taking  the  latter  view,  a  planet  above  its 
critical  temperature  is  all  gaseous.  Under  that  condition,  by  applying 
the  law  of  the  diffusion  of  gases,  you  have  each  gas  occupying  the  whole 
space  of  the  body  of  the  planet  as  if  the  other  gases  were  not  there. 


504  WATER   DISPLACEMENT   IN   OIL  AND    GAS   SANDS 

Gravitational  compression  will  produce  a  condition  of  density  greater 
than  that  of  the  solids  at  sufficient  depth,  so  that  when  such  a  planet 
cools,  the  solid  material,  being  lighter  than  the  highly  compressed  gases, 
will  act  just  as  if  it  were  a  solid  throughout.  You  still  have,  in  the  body 
of  the  planet,  some  of  each  of  the  gases  that  were  present  in  the  original 
planet  when  it  was  all  gaseous. 

As  regards  the  origin  of  petroleum  and  natural  gas,  there  is  just  the 
same  reason  for  the  hydrocarbons  being  in  that  gaseous  interior  as  any  of 
the  other  gases.  That  is  the  reason  why,  from  volcanoes,  all  the  known 
gases  of  the  atmosphere  and  others  are  extruded.  So  the  origin  of  helium 
goes  back  to  the  original  gaseous  planet,  like  the  origin  of  the  hydro- 
carbons. I  take  that  stand,  knowing  that  nearly  all  petroleum  engineers 
and  geologists  belie  vet  hat  petroleum  and  natural  gas  are  of  organic  origin. 

I  first  became  interested  in  this  matter  when  I  heard  Mr.  Eugene 
Coste  speak  on  the  subject.  He  did  not,  however,  go  back  as  far  as  that 
and  simply  denies  that  fossils  or  organic  matter  produce  oil.  I  can  see 
how  from  the  application  of  the  law  of  diffusion  of  gases  to  a  gaseous 
planet,  where  all  of  these  things  would  come  about  in  that  way,  the  oil  and 
gas  would  be  entirely  of  inorganic  origin.  In  the  question  whether  the 
dome  is  the  cause  of  the  accumulation  of  gas  or  the  gas  the  cause  of  the 
dome,  I  think  you  have  the  cart  before  the  horse.  I  think  the  domes  are 
caused  by  the  accumulation  of  gas,  the  gas  causing  the  dome  or  the  anti- 
cline or  both. 

DAVID  WHITE. — The  origin  of  the  helium  in  such  large  amounts  in 
the  natural  gas  of  parts  of  Ohio,  Kansas,  northern  Oklahoma,  and  Texas 
is  a  geological  problem  of  great  interest  and  importance  that  is  yet  to 
be  solved,  and  it  is  greatly  to  be  hoped  that  the  oil-  and  gas-field  geolog- 
ists will  find  the  key  to  the  situation.  There  is  some  circumstantial 
evidence  pointing  toward  the  occurrence  of  the  helium-rich  gas  of  Kansas 
and  Oklahoma  over  areas  of  deep-seated  faults  or  disturbance.  The 
same  may  be  true  of  the  north  Texas  region.  But  the  singular  fact  that 
the  helium  now  occurs,  in  general,  in  the  shallow  sands,  and  is  present 
only  in  relatively  small  amounts  or  not  at  all  in  the  deep  sands  in  most 
areas  is  baffling.  Apparently  the  Ohio  area,  Hocking  and  Vinton  Coun- 
ties, in  which  the  helium  is  found  in  the  Clinton  as  well  as  in  the  Berea, 
offers  no  exception.  One  does  not  look  for  badly  disturbed  rocks  in 
the  center  of  the  basin  in  southeastern  Ohio,  although  the  unexpected 
frequently  happens,  and  it  may  have  happened  in  this  case. 


COMPOSITION   OF   PETROLEUM  505 


Composition  of  Petroleum  and  Its  Relation  to  Industrial  Use 

BY  CHARLES  F.  MABERY,*  S.  D.,  CLEVELAND,  OHIO 

(New  York  Meeting,  February,  1920)  " 

So  FAB  as  the  elementary  composition  of  petroleum  is  known,  it 
may  be  briefly  stated.  Petroleum  consists  principally  of  a  few  series  of 
hydrocarbons,  with  admixtures  of  sulfur,  nitrogen,  and  oxygen  deriva- 
tives in  comparatively  minute  proportions,  which  may  be  regarded  as 
impurities  to  be  removed  in  the  preparation  of  commercial  products. 
But  as  each  series  is  represented  by  many  homologs,  in  the  aggregate, 
crude  petroleum  is  an  extremely  complex  mixture  of  hydrocarbons  and 
their  derivatives.  In  part,  these  hydrocarbons  individually  conform  in 
structure  to  the  system  of  synthetic  hydrocarbons  whose  structure  is 
well  defined  and  represented  by  the  typical  series  CnH2n+2,  CnH2n,  the 
series  CnH2n-2,  CnH2*_4,  the  members  of  which  have  not  been  suffi- 
ciently studied  to"  establish  their  structure,  and  the  series  CnH2n-6  com- 
posed of  the  aromatic  group,  benzene  and  its  homologs.  Hydrocarbons 
of  greater  density  contained  in  the  portions  of  petroleum  that  cannot  be 
distilled  without  decomposition  doubtless  have  less  hydrogen  than  is 
represented  by  these  formulas.  Since  to  every  hydrocarbon  there  is  a 
definite  temperature,  even  in  vacuum,  at  which  its  constituent  carbon 
and  hydrogen  atoms  fall  apart,  and  since  for  the  heavier  bodies  this  tem- 
perature is  not  much  above  360°  C.  in  vacuum,  it  is  evident  that  some 
other  method  than  distillation  must  be  devised  for  their  separation  if 
anything  further  is  to  be  learned  concerning  their  individual  constitution. 

CLASSIFICATION  OF  PETROLEUMS 

There  is  such  a  wide  variation  in  the  composition  of  petroleum  from 
different  fields,  it  would  seem  possible  to  make  a  classification  on  this 
basis  were  it  not  that  no  single  variety  is  entirely  free  from  hydrocarbons 
contained  in  others.  Such  a  classification  has  been  suggested  of  the 
exceptionally  pure  Pennsylvania  petroleum,  the  sulfur  oil  from  Trenton 
limestone  and  other  sources,  the  California  oil  with  its  large  amount 
of  nitrogen  (quinoline)  derivatives,  and  the  Russian  oil,  composed  chiefly 
of  the  naphthene  hydrocarbons.1  A  commercial  distinction  is  made 

*  Emeritus  Professor  of  Chemistry,  Case  School  of  Applied  Science. 
*&  F.  Peckham:  Jnl  Frank.  Inst.  (1896)  141,  219;  C.  Engler:  "Das  Erdol," 
1,  228.     Leipzig,  1913. 


506  COMPOSITION   OF   PETROLEUM 

between  oils  with  a  paraffine  base,  of  which  Pennsylvania  crude  is  typical, 
and  oils  with  an  asphaltic  base,  typical  Texas  and  California  crudes,  the 
heavier  varieties;  but  this  distinction  cannot  be  sharply  drawn  since 
there  are  oils  that  contain  both  constituents. 

Both  theoretically  and  commercially,  there  is  a  corresponding  differ- 
ence in  quality  between  such  light  oils  as  those  of  the  Appalachian  fields, 
some  of  them  composed  to  the  extent  of  50  per  cent,  or  more  of  gasoline 
and  kerosene  hydrocarbons,  and  almost  entirely  of  the  hydrocarbons 
CnHjn+2,  including  paraffine,  and  the  Texas  Gulf  oils  which  contain  no 
hydrocarbons  of  this  series  but  are  composed  of  heavy  members  of 
the  series  CnH2n_2,  and  CnH2rt-4,  besides  the  still  heavier  asphaltic 
bodies.  But  even  here  there  is  a  connecting  link  in  the  hydrocarbons 
of  the  series  CnH2,4-2  that  form  the  light  lubricants  of  the  Pennsylvania 
oil.  Such  interrelations  have  been  verified  in  all  American  petroleum. 
From  petroleum  of  many  fields  containing  sulfur  derivatives,  such  as 
that  of  the  Ohio  Trenton  limestone,  of  the  Illinois  fields  and  even 
of  Canada  with  large  sulfur  content,  there  are  good  yields  of  gasoline, 
kerosene,  and  paraffine.  The  great  fields  of  Oklahoma,  Kansas,  Wyom- 
ing, and  the  lighter  crudes  of  Texas  and  Louisiana  with  a  variable  com- 
position between  the  Appalachian  and  the  asphaltic  crudes  also  fall 
within  this  category. 

Petroleum  from  oil  territory  in  other  parts  of  the  world  does  not  differ 
materially  in  composition  from  that  of  the  American  fields.  The  princi- 
pal foreign  fields  are  those  of  Galicia,  Russia,  Rumania,  Japan,  and  the 
East  Indian  Islands.  They  contain,  in  variable  amounts,  paraffine, 
gasoline,  and  kerosene  hydrocarbons,  but  not  of  the  same  series  as  those 
of  American  gasoline  and  kerosene.  They  all  contain  sulfur  and  nitro- 
gen derivatives.  Rumanian  and  Japanese  oils  are  both  composed  to  a 
large  extent  of  the  naphthenes,  to  be  more  fully  described  later,  as  is  also 
Russian  oil  to  the  extent  of  80  per  cent,  or  more,  in  which  these  hydro- 
carbons were  first  identified.  Large  amounts  of  Russian  oil  have  been 
sold  here  for  medicinal  purposes,  but,  no  doubt,  some  varieties  of 
American  petroleum  are  fully  its  equal  in  this  field. 

BASIC  SERIES  OF  HYDROCARBONS 

Referring  again  to  the  basic  series  of  hydrocarbons  alluded  to  above 
as  constituting  the  main  body  of  American  petroleum,  the  series  CnH2n+2, 
commonly  known  as  the  methane,  or  marsh-gas,  series  for  it  begins  with 
methane  or,  marsh  gas,  CH4,  the  principal  component  of  natural  gas, 
is  the  most  comprehensive  for  it  includes  the  main  portions  of  gasoline, 
kerosene,  and  paraffine,  and  is  often  alluded  to  as  the  paraffine  series  and 
its  members  as  paraffine  hydrocarbons.  The  latter  increase  in  unit 
order,  by  the  increment  CH*,  through  the  more  volatile  gasolines  with 


CHARLES   F.    MABERY  507 

boiling  points  from  30°  to  150°  C.,  C6Hi2  to  C9H2o,  and  next  through 
kerosene,  with  boiling  points  from  150°  to  325°  C.,  C9H2o  to  CigEUo, 
when  they  soon  begin  to  solidify  as  parafftne  composed  of  the  crystalline 
hydrocarbons  from  C2oH42  to  C«5H72  and  distilling  in  vacuum  as  high 
as  350°  C.  In  practical  use,  these  hydrocarbons  include  paraffine  for 
candles,  kerosene  for  illumination,  and  the  lower  members  for  motor 
fuels,  and  various  minor  uses,  such  as  cleansers  and  solvents.  They  are 
extremely  inert,  entirely  devoid  of  lubricating  quality,  easily  decomposed 
by  heat  (cracked)  into  lower  members  of  the  same  series  or  into  unsatu- 
rated  hydrocarbons.  Such  decompositions,  which  include  also  other 
heavier  hydrocarbons,  are  the  basis  of  the  numerous  cracking  processes, 
in  which  heavy  oils  are  converted  into  more  volatile  forms  for  use  as 
motor  fuels. 

ETHYLENE  AND  NAPHTHENE  SERIES  OP  HYDROCARBONS 

Continuing  with  our  scheme  of  the  hydrocarbons,  the  next  paralle 
series  CnH2n,  the  ethylene  unsaturated  series,  is  present  in  small  amounts 
in  most  petroleum.  The  oil  that  separates  by  dilution  of  acid  sludge 
is  composed  to  a  considerable  extent  of  these  hydrocarbons,  for  they  are 
dissolved  by  the  acid  in  refining  the  crude  distillate.  It  was  formerly 
thought  that  these  bodies  formed  a  large  proportion  of  American  crude 
oil,  but  they  have  since  been  shown  to  be  another  series  of  the  same 
empiric  composition  and  formula,  CnH2n,  but  altogether  different  in 
properties;  they  are  cyclic,  or  closed-chain,  hydrocarbons  with  the  name 
naphthene,  proposed  by  Markownikoff,  who  first  discovered  them  in 
Russian  petroleum.  These  naphthene  hydrocarbons  are  probably  present 
in  all  petroleum  to  a  certain  extent,  in  small  amounts  in  the  light  Appa- 
lachian oils  and  in  larger  proportions  in  the  heavy  sulfur  and  asphaltic 
varieties.  They  form  a  considerable  part  of  light  American  gasolines, 
and  Russian  burning  oil  of  superior  luminosity  is  composed  altogether 
of  these  bodies.  Like  the  hydrocarbons  of  ,the  methane  series,  they 
are  devoid  of  lubricating  quality,  but  the  lower  members  form  good 
motor  fuels. 

HYDROCARBONS  HAVING  SOME  VISCOSITY 

The  next  series  of  hydrocarbons,  of  the  general  formula,  CnH2n_2, 
is  found  in  all  petroleum.  Collecting  in  the  fractions  above  300°  C.  and 
having  some  viscosity,  they  form  the  lubricants  in  Appalachian  petroleum 
that  are  prepared  for  sewing  machines,  typewriter  machines,  and  for 
other  similar  light  lubrication.  The  higher  members  of  this  series  are 
also  constituents  of  the  heavy  motor-car  lubricants.  Heavy  petroleum, 
in  general,  is  composed  to  a  large  extent  of  these  hydrocarbons;  but 
although  in  such  general  use,  their  structure  has  not  yet  been  ascertained. 


508  COMPOSITION   OF   PETROLEUM 

HYDROCARBONS  POSSESSING  HIGH  VISCOSITY 

Next  in  order  is  the  series  CnH2n_4,  made  up  of  hydrocarbons  possess- 
ing a  high  viscosity;  C25H46  is  one  of  them.  These  hydrocarbons  form  the 
constituents  of  the  best  lubricants  it  is  possible  to  prepare  from  petro- 
leum. Heavy  petroleum  with  an  asphaltic  base  contains  these  hydrocar- 
bons in  large  proportion,  and  lighter  varieties  in  smaller  amounts.  With 
boiling  points  above  250°  C.  in  vacuum,  the  decomposition,  when  dis- 
tilled with  dry  heat,  is  partly  prevented  by  the  use  of  steam  in  the  still  or, 
better,  by  excluding  air  and  reducing  the  boiling  points  by  exhaustion 
when  these  hydrocarbons  may  be  distilled  repeatedly  with  but  slight 
decomposition.  Straight  petroleum  lubricants  are,  therefore,  made  up 
mainly  of  a  few  viscous  hydrocarbons  of  the  last  two  series  mentioned,  and 
they  are  graded  by  varying  the  mixtures  to  provide  for  the  kind  of  lubri- 
cation desired. 

AROMATIC  HYDROCARBONS 

The  last  series  of  hydrocarbons  in  petroleum,  concerning  which  any- 
thing is  definitely  known,  is  represented  by  the  general  formula,  CnH2n_6 
or  the  so-called  aromatic  series,  beginning  with  benzene,  C6H6.  These 
hydrocarbons  are  contained  in  all  varieties  of  petroleum  so  far  as  known, 
but  in  only  minute  proportions  in  light  grades,  such  as  those  of  the 
Appalachian  fields.  Some  heavier  grades,  especially  those  of  California, 
contain  large  amounts  of  the  aromatic  hydrocarbons — benzene,  toluene, 
the  xylenes,  mesitylene,  and  naphthalene  has  been  observed.  But  these 
bodies  are  rather  a  detriment  in  petroleum  to  be  removed  in  the  processes 
of  refining.  They  are  closely  related  to  the  cyclic  naphthenes  in  struc- 
ture, the  latter  partaking  of  the  properties  of  both  the  methane,  or  paraf- 
fine,  series  and  the  aromatic  series.  For  instance,  by  the  addition  of 
hydrogen,  benzene  unites  with  six  atoms  to  form  hexahydro-benzene 
C6Hi2,  and  from  the  latter  by  proper  treatment  the  six  atoms  of  hydrogen 
may  be  removed  to  form  the  same  benzene.  The  same  relation  holds  for 
all  the  homologs  of  benzene  and  their  hexahydro  derivatives. 

OXYGEN  COMPOUNDS  OF  PETROLEUM  HYDROCARBONS 

Of  the  oxygen  compounds  of  the  petroleum  hydrocarbons,  phenols 
are  found  in  some  heavy  varieties,  such  as  California  oil,  and  the  naph- 
thene  acids  first  discovered  in  Russian  oil,  which  contains  them  in  con- 
siderable amounts,  are  generally  to  be  found.  But  they  have  no 
influence  on  commercial  products  for  they  are  removed  by  proper 
refining,  although  it  is  probable  that  they  have  something  to  do  with  the 
formation  of  emulsions. 


CHARLES  F.  MABEBY  509 

NITROGEN  BASES 

The  nitrogen  bases,  the  quinolines,  are  contained  in  all  petroleum,  in 
some  varieties  in  large  proportions;  it  has  been  estimated  that  some 
California  petroleums  contain  as  much  as  10  to  20  per  cent.;  but  they  also 
are  completely  removed  in  refining.  These  bases  are  of  especial  interest 
in  their  bearing  on  the  origin  of  petroleum  as  indicating  its  evolution 
from  organic  remains,  animal  or  vegetable. 

SULFUR  IN  PETROLEUM 

Sulfur  is  the  most  undesirable  impurity  in  petroleum,  and  it  is  pretty 
nearly  everywhere  present,  except  in  the  Appalachian  oils  and  in  certain 
heavy  oils  from  shallow  wells.  In  general,  it  appears  that  the  proportion 
of  sulfur  has  considerably  diminished  as  compared  with  the  quantities 
contained  in  the  earlier  development  of  oil  territory.  The  largest  pro- 
portion that  has  come  under  my  observation  is  2.75  per  cent,  in  the  early 
Humble  crude,  about  one-third  free  sulfur  in  solution,  nearly  all  that  the 
crude  oil  can  hold,  and  two-thirds  combined.  Formerly,  the  free  sulfur 
often  crystallized  out  in  the  tank  cars  during  transportation;  now  the 
amount  in  this  oil  is  less  than  1  per  cent.  Sulfur  was  first  observed  in 
Canadian  oil  at  Petrolia,  which  carried  1  per  cent.,  next  in  Ohio  Trenton 
limestone  oil  in  the  late  eighties,  containing  1  per  cent,  or  less;  and  more 
recently  in  the  fields  of  Illinois,  Oklahoma,  Louisiana,  Kansas,  and 
Wyoming  containing  variable  proportions  below  0.5  per  cent.  In 
combination  with  the  hydrocarbons,  sulfur  derivatives  are  of  the  form 
CnH2nS,  such  as  the  individual  Ci0H2oS,  unstable  when  heated  in  contact 
with  air,  but  distilled  without  decomposition  in  vacuum.  Their  struc- 
ture is  uncertain  but  probably  cyclic  with  sulfur  the  connection  link. 
Since,  as  in  Texas,  where  wells  are  often  drilled  through  beds  of  sulfur 
with  which  the  oil  has  long  been  in  contact,  it  is  not  difficult  to  understand 
its  mechanical  solution. 

In  the  ordinary  refining  of  petroleum,  sulfur  is  removed  only  in  part, 
necessitating  the  use  of  special  methods  for  its  removal  to  the  extent  that 
it  should  contain  not  more  than  0.05  per  cent,  in  burning  oil  to  avoid 
SO 2  in  the  atmosphere  of  the  compartment,  and  not  in  excess  of  0.1  per 
cent,  in  lubricants,  to  avoid  corrosion  of  metals.  Distillation  over  copper 
oxide  or  metallic  iron  is  the  usual  method  of  removal  where  the  amount 
of  sulfur  is  large.  The  presence  of  combined  sulfur  in  petroleum  has 
an  especial  interest  to  the  geologist,  for  it  is  doubtless  associated  with  the 
primary  formation  of  the  heavier  varieties.  Such  large  amounts  as 
petroleum  contain  could  not  have  had  an  origin  in  vegetable  or  animal 
matter;  it  must  have  been  the  result  of  secondary  changes,  in  which  the 
oil  came  in  contact  with  beds  of  sulfur,  the  latter  having  been  formed  from 


510  COMPOSITION   OF   PETROLEUM 

sulfates  in  underground  sulfate  water  by  reduction  of  organic  matter. 
When  heated  with  sulfur,  the  hydrocarbons  readily  give  off  hydrogen 
sulfide  and  under  proper  conditions  the  sulfur  combines  with  the  hydro- 
carbons. These  changes  no  doubt  explain  in  part  the  principal  differ- 
ence between  the  light  oils  of  the  Appalachian  region,  which  have  never 
been  in  contact  with  sulfur,  and  the  heavier  varieties  of  the  middle  west 
and  south,  which  have  always  been  associated  with  sulfate  waters. 
The  former  are  nearly  pure  mixtures  of  hydrocarbons,  the  lighter  individuals 
predominating,  and  of  the  most  stable  series,  such  as  is  known  to  be 
experimentally  formed  from  the  decomposition  of  vegetable  or  animal 
matter,  containing  only  small  amounts  of  sulfur.  Derived  from  vege- 
table matter  in  the  Appalachian  region,  far  removed  from  the  organic 
remains  of  the  ancient  sea  that  left  the  great  saline  beds  of  the  middle 
west  between  the  Appalachian  and  the  Rocky  Mountains  and  far  away 
from  contact  with  the"  sulfur  or  sulfates  of  those  deposits,  this  petroleum 
may  be  regarded  as  the  typically  pure  product  of  vegetable  organic  decay 
with  exclusion  of  air. 

The  conditions  were  very  different  in  the  formation  of  the  heavier 
varieties  of  Ohio,  Illinois,  Oklahoma,  and  Kansas  in  the  great  sea  bed 
of  this  region.  Concurrent  with  the  decay  of  sea  life  yielding  oil,  or  sub- 
sequently it  may  be,  and  with  an  increase  in  temperature,  came  the  action 
of  sulfur  removing  hydrogen,  increasing  the  density  of  the  oil  and  intro- 
ducing sulfur  in  combination.  This  sharp  demarcation  between  the 
formation  of  the  Appalachian  and  middle  west  petroleum  is  sufficient 
to  account  for  these  differences  in  composition  and  properties.  Changes 
subsequent  to  the  formation  of  Appalachian  oil,  of  moderate  temperature, 
pressure,  possible  transference  or  infiltration  through  different  strata  in 
many  periods  of  decomposition,  elevation  and  folding,  all  combined  to 
produce  an  oil  unlike  in  purity  that  of  any  other  field.  The  heavier 
quality  of  Trenton  limestone  petroleum,  doubtless  due  in  part  to  its 
origin  from  the  same  source  as  the  lime  rock,  was  increased  by  the  action 
of  sulfur  in  the  formation  of  the  compounds  it  now  contains. 

For  the  original  formation  of  California  petroleum  the  records  are 
plainly  written  in  the  great  beds  of  marine  shell  life,  asserted  by  Doctor 
Dickenson  to  be  an  adequate  source  of  all  petroleum  in  those  extensive 
fields.  As  in  other  oil  territory  of  similar  origin,  most  of  this  petroleum  is 
thick  and  heavy,  lacking  altogether  the  lighter  constituents  of  deposits  de- 
rived from  a  vegetable  source.  It  contains  much  sulfur,  indicating  that 
this  element  had  something  to  do  in  the  formation  of  its  heavy  condition, 
much  nitrogen  in  the  form  of  quinolines,  and  a  large  proportion  of  heavy 
asphaltic  hydrocarbons — the  asphalt  base.  That  it  contains  much  organic 
matter  not  fully  converted  into  the  petroleum  hydrocarbons  is  shown  by 
the  maggoty  condition  of  some  of  the  oil  pools.  On  the  other  hand, 
there  is  evidence  that  this  petroleum  has  been  subject  to  none  of  the 


CHARLES   P.    MABERY  511 

secondary  changes  that  have  contributed  to  the  clarifying  effects  of  the 
eastern  deposits — that  it  has  been  changed  little,  if  at  all,  in  the  location 
of  its  origin.  A  possible  contribution  to  the  formation  of  California 
petroleum,  and  it  may  be  to  other  petroleum,  is  suggested  by  what  has 
taken  place  in  the  Rancho  La  Brea  asphalt  pits,  and  the  interesting 
collection  in  the  museum  at  Los  Angeles  of  animal  skeletons  representing 
all  the  extinct  mammalian  fauna  of  that  region  caught  in  those  pits  in 
the  glacial  epoch  that  terminated  25,000  years  ago  after  a  probable  dura- 
tion of  500,000  years. 

HEAVY  OHIO  OIL 

Besides  the  varieties  of  petroleum  already  described,  there  is  another 
essentially  different  in  its  composition  and  quality,  in  fact  almost  a  class 
by  itself.  As  Appalachian  petroleum,  composed  of  a  pure  mixture  of 
hydrocarbons,  stands  at  the  end  of  a  series  with  the  lighter  individuals 
predominating,  so  this  oil  may  be  regarded  as  the  other  end  of  the  series, 
also  a  pure  mixture  of  hydrocarbons  but  of  the  least  volatile  end.  It 
has  none  of  the  gasoline  nor  kerosene  constituents,  none  of  thenaphthenes, 
no  paraffine  nor  asphaltic  base.  This  Ohio  oil  is,  doubtless,  of  more 
recent  origin  than  most  other  petroleum,  and  it  has  never  been  in  con- 
tact with  sulfur.  It  has  been  found  in  three  localities  not  far  removed. 
One  is  a  depression  on  the  Mahone  River,  in  quartz  sand  150  ft.  (45  m.) 
deep,  the  oil  overlying  a  pool  of  brine  and  closely  adjacent  to  large  beds 
of  coal.  Just  when  the  commercial  development  of  this  oil  territory 
had  begun,  the  entire  area  was  flooded  with  water  by  a  water  company. 

A  second  field  of  similar  character  is  the  ancient  Mecca  district,  one 
of  the  first  in  this  country  to  be  operated  on  a  commercial  scale  on  account 
of  its  use  as  a  natural  lubricant.  This  oil  has  also  been  long  known  for  its 
medicinal  quality.  But  since  it  contains  neither  gasoline  nor  kerosene 
hydrocarbons  its  output  has  been  much  restricted.  The  greatly  increased 
demand  for  lubricants  has  again  attracted  attention  to  this  oil,  and  it  is 
now  being  systematically  pumped  for  the  manufacture  of  high-grade 
lubricants.  The  wells  are  shallow,  70  to  100  ft.  (21  to  30  m.)  deep,  and 
the  oil  is  taken  from  a  surface  of  brine. 

A  third  field  of  the  same  general  type  is  near  Middlebranch,  Ohio, 
likewise  in  a  shallow  depression  of  a  few  hundred  acres;  the  oil  is  here 
reached  in  wells  about  700  ft.  deep,  also  above  salt  brine.  For  some  time 
this  field  yielded  a  large  supply  of  gas,  which  is  still  utilized  in  considera- 
ble quantity.  Both  these  oils,  like  the  Mahone,  are  of  more  recent  origin 
than  those  of  other  fields,  and  they  have  undergone  no  other  metamorpho- 
sis by  the  influence  of  sulfur  or  changes  in  location  than  the  apparent 
evaporation  of  the  volatile  end — gasoline  and  kerosene  hydrocarbons. 
Thus  in  nature's  laboratory  through  long  periods  of  time  this  oil,  com- 


512  COMPOSITION   OF   PETROLEUM 

posed  of  a  few  hydrocarbons  of  maximum  viscosity,  has  been  formed  and 
preserved,  and  now  with  proper  treatment  it  yields  lubricants  of  the  best 
quality  it  is  possible  to  prepare  from  petroleum.  Since  the  crude  oil  has 
a  viscosity  of  3000  sec.,  a  specific  gravity  of  0.90  at  20°  C.,  and  all  the 
hydrocarbons  it  contains,  except  5  per  cent,  of  the  lighter  end,  having 
marked  viscosity,  in  the  treatment  of  the  oil  in  refining,  it  is  only  neces- 
sary to  select  the  hydrocarbons  for  the  viscosity  desired,  without  decom- 
position, and  to  give  the  resulting  oil  a  proper  finish.  The  lubricant 
value  of  this  petroleum  is  explained  by  its  composition.  Containing  none 
of  the  paraffine  hydrocarbons,  none  of  the  naphthenes,  it  is  composed 
chiefly  of  the  two  series  CnH2n-2  and  CnH2n-4,  both  of  high  lubricant 
quality.  As  to  the  composition  of  the  hydrocarbons  beyond  the  range  of 
distillation  without  decomposition,  nothing  is  known;  these  residues 
still  retain  their  viscosity  without  the  ready  formation  during  distilla- 
tion of  asphaltic  products  common  to  most  heavy  petroleum. 

For  a  more  complete  resume  of  the  composition,  geology,  occurrence, 
genesis,  and  technology  of  American  petroleum  reference  is  made  to  a 
paper  by  Clifford  Richardson,2  a  paper  by  C.  F.  Mabery3  and  the  most 
complete  work  on  American  petroleum  industry  that  has  appeared,  by 
Bacon  and  Hamor.4  In  1915,  David  White,5  of  the  U.  S.  Geological 
Survey,  gave  a  very  complete  review  of  the  data  from  extensive  observa- 
tions and  their  bearing  on  the  relations  in  formation  of  coal  and 
petroleum. 

PREPARATION  OF  COMMERCIAL  PRODUCTS  FROM  PETROLEUM 

There  has  been  little  fundamental  change  in  the  refining  of  petroleum 
since  the  early  days  of  this  industry.  The  first  stage  in  the  process  is 
distillation,  to  separate  the  cuts,  or  distillates,  that  are  to  be  used  for 
gasoline,  kerosene,  and  lubricants.  Until  recently,  these  cuts  were  made 
by  specific  gravity  of  the  distillate  at  the  end  of  the  condensers;  now 
pyrometers  set  into  the  stills  give  a  fairly  good  separation  by  recording 
temperatures.  To  avoid  the  decompositions  of  outside  heat  alone,  live 
or  superheated  steam  is  now  freely  used  within  the  still. 

There  is  always  a  certain  amount  of  decomposition  products  in  the 
distillates,  besides  the  natural  impurities  in  the  crude  oil,  so  the  next  stage 
has  always  been  to  agitate  with  concentrated  sulfuric  acid,  which  removes 
these  bodies  as  a  heavy  acid  sludge  that  is  drawn  off  after  standing  some 
time  to  settle.  Another  process,  which  has  found  limited  use,  consists 

» Jrd.  Frank.  Inst.  (1906)  162,  57,  81. 
'Mabery:  Jnl  Amer.  Chem.  Soc.  (1906)  28,  415. 

4  R.  F.  Bacon  and  W.  A.  Hamor:  "American  Petroleum  Industry."  N.  Y.,  1916, 
McGraw-Hill. 

'  Jnl.  Wash.  Acad.  Sci.  (1915). 


CHARLES   P.    MABERY  513 

in  agitating  with  liquid  sulfurous  acid,  but  this  process  has  not  been 
generally  adopted. 

For  the  complete  removal  of  the  acid  sludge  and  acid  compounds  in 
solution,  the  next  operation  consists  of  agitation  with  caustic  soda  in 
sufficient  excess  to  neutralize  the  acid.  Since  a  very  slight  excess  of  the 
caustic  causes  an  emulsion  of  the  oil,  this  stage  of  the  treatment  demands 
the  best  skill  and  care  on  the  part  of  the  man  in  charge  of  the  treating 
house,  with  the  aid  of  the  works  chemist.  It  is  not  possible  to  work  by 
definite  formula,  because  the  wide  difference  in  the  distillates  from  crudes  of 
different  fields  requires  varying  amounts  of  caustic.  The  formation  of 
emulsions  is,  and  always  has  been,  the  worst  trouble  with  which  the  refiner 
must  contend,  for  it  means  loss  of  oil,  besides  the  additional  labor,  and 
a  darkening  of  the  finished  oil  through  the  application  of  heat,  which 
alone  will  break  up  an  emulsion.  In  such  oil  emulsions,  minute  particles 
of  aqueous  alkali  are  completely  enclosed  within  films  of  oil  and  retained 
almost  indefinitely  at  ordinary  temperatures.  Washing  the  emulsion 
merely  increases  its  volume  by  the  absorption  of  more  water.  On  the 
other  hand,  if  caustic  is  not  used  in  sufficient  excess  to  remove  the 
sludge,  there  is  danger  of  an  objectionable  color  as  well  as  an  acid  condi- 
tion in  the  finished  oil.  There  is  more  danger  of  emulsions  in  finishing 
heavy  distillates.  In  the  last  stage  of  refining,  the  dry  oil  is  passed 
through  Fuller's  earth  to  lighten  its  color. 

PRODUCTION  AND  USE  OF  GASOLINE 

At  first,  kerosene  was  the  principal  product  refined  from  petroleum, 
with  a  limited  use  of  gasoline,  as  a  solvent  and  for  cleansing,  and  of  the 
heavy  distillates.  Later,  with  the  adaptation  of  acetylene  and  the  cheap- 
ening of  electricity  for  both  city  and  country  lighting,  the  demand  for 
kerosene  diminished  to  such  an  extent  that,  just  before  the  war,  the  refiner 
informed  the  seller  of  gasoline  that  he  must  take  a  certain  proportion  of 
kerosene  with  his  gasoline.  The  use  of  gasoline  had  already  rapidly 
increased,  on  account  of  the  adaptation  of  the  stationary  gasoline  engine 
for  power;  and  when  the  economic  efficiency  of  the  gasoline  engine  was  so 
perfected  that  it  could  be  used  for  motive  power  in  the  automobile  and 
a  popular  demand  for  motor  cars  was  established,  the  consumption 
increased  to  such  an  extent  that  the  output  of  crude  oil,  although  very 
greatly  enlarged,  could  not  meet  the  demand.  Then  appeared  numerous 
attempts  and  many  patents  were  obtained  for  the  production  of  motor 
oil  by  cracking  the  higher  hydrocarbons  into  lighter  oils  that  could  be 
used  in  motor  engines. 

Even  now  it  appears  that  the  production  cannot  keep  pace  with 
consumption,  and  that,  as  reported,  reserve  supplies  are  being  drawn 
upon  to  maintain  a  demand  that,  in  large  part,  serves  no  economic  nor 

VOL.   LXV. — 33. 


winds,  and  si 
and   convenience 
of  coal  and  petrol 


Next  in  imj 
nomic  application! 
over  another, 
butes  of  matter, 
in  view  in  all  mecl 


CHARLES   P.    MABERY  515 

prevent  such  friction  and  that  is  to  avoid  contact,  but  it  is  possible 
of  control  within  the  limits  of  economic  mechanical  operation  by  the 
insertion  of  a  third  body  capable  of  bearing  the  moving  weight.  Such  a 
body  is  known  as  a  lubricant  and  the  lubricating  materials  are  restricted 
to  solids,  the  softer  metals,  graphite  and  certain  other  unctuous  sub- 
stances like  talc,  and  some  oils  and  greases.  A  hard  metal  bearing  on  a 
softer  metal  may  be  lubricated  to  some  extent  by  the  softer  metal,  but 
the  nearest  approach  to  an  ideal  solid  lubricant  is  pure  graphite,  which 
forms  a  veneer  on  a  hard  surface,  closing  the  pores  and,  by  means  of 
its  highly  unctuous  quality,  reducing  friction  to  the  lowest  possible 
limit.  Of  oil  lubricants,  the  undecomposed  petroleum  hydrocarbons  with 
impurities  removed  possess  the  best  wearing  quality.  They  lubricate 
until  the  last  molecule  is  used  up.  Certain  vegetable  and  animal  oils 
have  the  requisite  viscosity,  but  they  are  less  stable,  gum  and  corrode  by 
decomposition,  and  are  inferior  in  durability. 

In  the  preparation  of  petroleum  lubricants,  the  grade  must  be  se- 
lected with  reference  to  the  work  that  it  is  expected  to  perform,  first  in  the 
cuts  of  the  distillation  and  then  in  the  combination  of  the  hydrocarbons 
for  the  quality  desired.  The  principal  means  of  control  are  specific 
gravity,  viscosity,  and  the  heat  quality,  as  represented  by  the  tests  of 
flash  and  fire.  As  factors  of  safety,  the  fire  tests  and  especially  the  flash 
test,  must  be  closely  controlled  in  oils  designed  for  motor-engine  lubri- 
cation and  made  to  conform  to  established  safety  limits — for  water-cooled 
engines  250°  F.  (120°  C.)  and  for  air-cooled  engines  350°  F.  These  tem- 
peratures of  the  cylinders  should  be  exceeded  by  the  flash  points  of  the 
lubricant  oils  by  at  least  50°  F.  For  steam  cylinders,  lubricants  must 
have  a  flash  of  500°  to  650°  F. 

The  actual  value  of  a  lubricating  oil  is  based  on  its  viscosity — the 
peculiar  quality  of  oiliness  or  greasiness  that  holds  the  molecules  together 
with  sufficient  force  to  maintain  the  pressure  of  the  surfaces  they  hold 
apart.  The  viscous  quality  is  wanting  in  the  paraffine  hydrocarbons 
CnH2n+2  and  in  the  naphthenes  CnH2n.  It  appears  in  the  series  CnH2n_2; 
and  of  the  distilled  lubricants,  reaches  its  highest  value  in  the  series 
CnH2*_4.  In  heavy  crudes,  such  as  those  of  Texas  and  California,  the 
lubricating  quality  ends  with  the  distillates  from  the  asphaltic  residues, 
and  only  partly  appears  in  the  paraffine  residue  of  the  lighter  crudes.  But 
in  the  heavy  Mecca  oil,  all  but  a  few  hydrocarbons  of  the  first  distillate, 
not  more  than  5  per  cent.,  are  decidedly  viscous,  the  viscosity  increasing 
rapidly  and  continuing  throughout  the  entire  mass  of  the  oil,  such  that 
the  residue  of  vacuum  distillation  has  an  extremely  high  viscosity.  Thus, 
it  is  possible  to  prepare  from  this  crude  oil  a  wide  range  of  lubricants; 
beginning  with  the  light  oils  needed  for  sewing  machines  and  type- 
writer machines,  watch  and  clock  oils,  through  the  various  grades  of 
motor-oil  lubricants,  heavy-engine  and  steam-cylinder  oils. 


516  COMPOSITION   OF  PETROLEUM 

Next  to  the  production  of  power  in  a  motor  car,  the  most  important 
detail  in  its  operation,  and  one  that  is  too  much  neglected,  is  lubrication. 
Too  often  the  car  owner  has  not  the  slightest  knowledge  as  to  what  sort  of 
lubricant  is  best  adapted  to  his  car;  he  uses  what  is  given  him  or  what  he 
is  advised  to  use,  which  is  often  too  low  in  viscosity.  An  oil  that  seems 
very  oily  at  ordinary  temperature  may  become  as  thin  as  water  when 
exposed  to  the  great  heat  of  the  cylinders.  Excepting  perhaps  the  lightest 
cars,  all  others  should  be  run  on  lubricants  with  a  viscosity  of  at  least  1000 
to  1200  sec.,  Universal  viscosimeter,  and  the  oil  should  not  be  used  until 
it  becomes  too  thin.  There  is  doubtless  greater  unnecessary  wear  in 
motor  cars  from  lack  of  lubrication  than  from  any  other  neglect. 

Of  the  many  annoyances  in  the  operation  of  a  motor  car,  one  of  the 
most  serious  is  the  necessity  for  frequent  removal  of  carbon  from  the 
cylinders,  on  account  of  its  interference  with  the  passage  of  the  spark 
for  the  explosion  and  its  deadening  effect  on  the  resulting  power.  De- 
posits of  carbon  may  be  formed  from  the  lubricant  and  from  the  gaso- 
line. With  the  use  of  normal  gasoline,  a  lubricant  properly  refined  and 
adapted  to  the  size  of  the  engine,  to  its  load,  and  the  conditions  of  its 
use,  it  is  safe  to  say  that,  with  proper  manipulation,  smoking  exhausts 
should  disappear  and  carbon  deposits  be  reduced  to  a  minimum,  or  easily 
removed  by  such  simple  expedients  as  pouring  gasoline  into  the  engine 
while  hot. 

The  common  use  of  too  light  lubricants  in  motor  cars  is  poor  economy, 
as  well  as  the  use  of  the  same  grade  in  all  cars,  irrespective  of  their  weight. 
No  doubt  the  quality  of  the  lubricant  as  well  as  the  quality  of  the  gasoline 
has  much  to  do  with  carbonization.  Cracked  gasoline,  consisting  of 
partly  decomposed  hydrocarbons,  more  readily  escapes  complete  com- 
bustion, sending  forth  dense  fumes,  a  sure  indication  of  excessive  carbon 
deposits.  Yet  with  a  sufficient  excess  of  air  and  an  adequate  temperature 
for  complete  combustion  in  the  cylinders,  even  these  hydrocarbons  may 
be  completely  burned,  leaving  behind  little  carbon. 

An  exaggerated  importance  is  attached  to  what  is  termed  "free  carbon  " 
in  motor  lubricants,  a  misleading  term,  based  on  the  differences  in  the 
carbon  residue  of  a  loose  method  of  determination,  which  consists  in 
evaporating  the  oil  until  a  mixture  of  free  carbon  and  hydrocarbons  re- 
main, the  latter  not  completely  expelled  by  heat  in  this  manner.  It  is 
assumed  that  the  results  indicate  the  comparative  extent  to  which  dif- 
ferent oils  form  carbon  in  an  engine.  But  on  account  of  other  elements 
of  operation,  as  well  as  the  fact  that  carbon  deposits  consist  to  a  con- 
siderable extent  of  mineral  matter,  sometimes  as  much  as  70  per  cent., 
the  tendency  to  leave  carbon  in  analytical  determinations  has  little 
bearing  on  the  comparative  value  of  lubricants  with  reference  to  carbon 
deposition.  Some  of  the  best  lubricants,  as  regards  carbon  deposits  in 
the  cylinders,  give  higher  percentage  of  "free  carbon"  in  the  analytical 
determinations  than  others  that  carbonize  more  freely  in  the  engine. 


DISCUSSION  517 

UTILIZATION  OF  OTHER  PETROLEUM  SOURCES 

With  the  present  abundant  and  convenient  supply  of  petroleum,  it  is 
not  yet  necessary  to  earnestly  cast  about  for  other  forms  of  bitumen  as 
sources  of  commercial  products  most  in  demand.  But  we  are  assured 
that  the  great  deposits  of  rich  carboniferous  shales  in  the  west  only  await 
a  serious  falling  off  in  petroleum  production  to  provide  a  practically 
unlimited  output  of  motor-engine  and  lubricating  oils,  not  perhaps  of  the 
equivalent  value  of  petroleum  products  but  good  substitutes. 

Closely  related  to  petroleum  as  to  their  origin  and  oils  they  yield  by 
distillation,  are  certain  other  varieties  of  bitumen  found  in  Colorado  and 
Utah — Gilsonite  and  Grahamite.6  These  natural  asphaltic  bitumens 
still  contain  a  considerable  proportion  of  volatile  oils,  the  lighter  portions 
having  evaporated  during  their  slow  formation  from  petroleum  leaving 
these  brittle  solids  resembling  coals.  But  unlike  coals  containing  the 
inorganic  residue  of  their  primary  vegetable  formation,  Gilsonite  and 
Grahamite,  owing  their  genesis  through  secondary  phases  to  petroleum, 
are  free  from  all  inorganic  residues. 

As  recently  as  twelve  years  ago,  petroleum  that  could  not  produce 
kerosene,  such  as  that  of  Texas  and  California,  was  of  lower  commercial 
value  and  in  demand  only  for  fuel,  or  for  a  limited  production  of  lubricants. 
Very  soon  the  rapid  development  of  the  automobile  industry,  stimulating 
a  demand  for  gasoline  and,  consequently,  for  lubricants,  gave  greater 
prominence  to  the  heavy  crudes,  both  as  a  source  of  lubricants  and  of 
motor  fuels  by  cracking  the  higher  hydrocarbons.  But  with  production 
pushed  to  the  utmost,  the  older  fields  alone  could  not  have  prevented  a 
gasoline  famine  during  the  war,  with  serious  results.  When  in  1917  the 
English  Admiralty  was  confronted  by  defeat  within  three  months  unless 
it  could  halt  the  submarine  destruction,  the  situation  was  saved  by  the 
contributory  influence  of  the  great  increase  in  the  output  of  motor  fuel 
from  the  new  fields  of  Illinois,  Oklahoma,  Kansas,  Wyoming,  and  Mexico, 
all  but  the  latter  yielding  large  amounts  of  normal  gasoline.  With 
the  material  falling  off  in  production  of  the  Appalachian  fields,  the  new 
territory  came  in  at  an  opportune  moment  to  meet  the  demands  of  the 
war  and  the  great  expansion  of  the  automobile  industry. 

VALUE  OF  SCIENTIFIC  WORK 

Much  of  the  loss  in  the  early  days  of  the  petroleum  industry  due  to 
haphazard  prospecting  and  drilling  was  later  avoided  by  the  scientific 
investigations  of  geologists,  especially  by  Hunt,  Orton,  Winchell,  New- 
berry,  and  Hoef  er.  From  the  prospector's  point  of  view,  the  most  impor- 
tant of  all  was  the  theory  of  Hunt  suggesting  the  storage  of  oil  in  an  anti- 

6Mabery:  Jrd.  Amer.  Chem.  Soc.  (1917)  392,  2025. 


518  COMPOSITION   OF   PETROLEUM 

clinal  and  synclinal  system,  and  referring  the  great  rock  pressure  on  oil 
and  gas  to  an  extensive  underground  hydraulic  system.  In  the  later  ap- 
plication and  expansion  of  this  theory,  the  storage  of  oil  in  all  the  great 
fields  of  the  world  was  found  to  be  in  well-defined  anticlines.  When  the 
Trenton  limestone  was  identified  by  Orton  as  the  reservoir  of  the  immense 
deposits  of  oil  in  Ohio  and  Indiana,  he  established  such  an  extended 
system  of  anticlinal  storage  of  gas  and  oil  that  the  direction  of  the  dip 
could  be  traced  with  sufficient  accuracy  to  direct  the  prospector  in  his 
drilling  operations.  Furthermore,  Orton  identified  the  dolomitic  nature 
of  the  oil-bearing  rock  and,  by  means  of  outcropping  rock  formation, 
indicated  the  underlying  strata  that  could  be  relied  on  as  sources  of  gas 
and  oil  storage. 

What  geological  science  has  done  in  placing  the  exploitation  of  petro- 
leum territory  on  a  practical  and  successful  economic  basis  has  its  partial 
counterpart  in  the  results  of  chemical  research.  What  is  known  con- 
cerning the  chemistry  of  petroleum  is  the  result  of  independent  investi- 
gations carried  on  in  the  limited  facilities  of  the  chemical  laboratory, 
altogether  unlike  the  opportunities  of  the  geologist  who  always  had  the 
advantage  of  unrestricted  observations  at  fundamental  sources.  If, 
in  the  early  development  of  the  petroleum  industry,  there  had  been  estab- 
lished a  properly  organized  refinery  with  adequate  funds  and  an  adequate 
working  force  to  ascertain  the  complete  composition  of  crude  oil  from 
the  producing  fields  then  known,  and  to  take  up  thorough  investigation 
of  newly  discovered  territory  as  it  came  into  commercial  prominence,  the 
gain  to  the  present  and  future  industry  would  have  been  beyond  calcula- 
tion. Even  now,  before  oil  territory  is  too  far  exhausted  and  abandoned, 
such  an  organization  should  place  on  record  a  great  accumulation  of  facts  as 
to  the  constituents  of  petroleum  concerning  which  little  or  nothing  is  known, 
and  which  should  incidentally  be  of  service  to  the  petroleum  industry. 

DISCUSSION 

SAMUEL  P.  SADTLEE,  Philadelphia,  Pa.  (written  discussion). — I 
have  read,  with  great  interest,  this  discussion  on  the  individual  series  of 
hydrocarbons  that  are  found  to  be  represented  in  natural  petroleums. 
One  of  the  subjects  of  very  great  practical  interest  is,  what  hydrocarbons 
possess  special  viscosity.  Doctor  Mabery  very  properly  calls  attention 
to  the  class  of  hydrocarbons  that  seem  to  be  characteristic  of  the  lubri- 
cants prepared  from  Appalachian  petroleum.  These,  he  states,  are 
higher  members  of  the  series  C«H2n-2-  He  does  not  particularize  as  to 
which  kind  of  hydrocarbons  of  this  general  formula  he  means.  It  is 
obvious  that  they  are  not  the  hydrocarbons  of  the  acetylene  series,  but 
of  what  are  termed  unsaturated  cyclic  hydrocarbons,  also  possessing 
this  formula. 


DISCUSSION  519 

He  calls  attention  to  the  hydrocarbons  of  the  series  C»H2n-4  as  possess- 
ing high  viscosity.  Here  again,  it  is  proper  to  understand  that  reference 
is  made  to  unsaturated  cyclic  hydrocarbons,  as  distinguished  from  alipha- 
tic hydrocarbons,  and  he  practically  awards  the  whole  value  for  lubricat- 
ing power  in  prepared  oils  to  hydrocarbons  belonging  to  these  series. 

He  specifically  states  also,  on  page  507,  of  the  naphthenes,  first 
recognized  in  Russian  petroleum,  and  now  known  to  be  present  in  most 
American  petroleums,  that,  "like  the  hydrocarbons  of  the  methane  series, 
they  are  devoid  of  lubricating  qualities. "  This  rather  positive  statement 
of  Doctor  Mabery's  is  probably  not  a  matter  that  is,  as  yet,  univer- 
sally agreed  upon.  The  studies  that  have  been  made  upon  this  subject 
in  recent  years,  largely  by  the  aid  of  the  "formolite"  reaction,  do  not 
as  yet  give  conclusive  evidence  on  this  subject. 

Engler,  in  his  work  on  the  chemistry  of  petroleum,  says  (1,  387): 
"The  controversial  question  as  to  which  group  of  hydrocarbons  are  the 
chief  bearers  of  the  viscosity,  which  has  recently  been  especially  studied 
on  the  one  hand  by  Nastjukoff,  as  well  as  Herr,  who  take  the  view  that 
the  viscosity  belongs  to  the  unsaturated  oils,  and  on  the  other  hand  by 
Charitschkoff ,  who  attributes  it  also  to  the  saturated  naphthenes,  is  not 
yet  definitely  decided.  That  the  unsaturated  cyclic  hydrocarbons  of  high 
molecular  weight  are  also  highly  viscous  is  settled  beyond  doubt,  as  is 
conceded  also  by  Charitschkoff.  It  is,  however,  not  yet  shown  that  the 
high  molecular  saturated  cyclic  hydrocarbons  are  not  also  very  viscous. " 

On  page  558,  Engler  quotes  a  series  of  relatively  recent  results  by 
Marcusson,  which  were  obtained  by  the  study  of  both  American  and 
Russian  oils.  These  results  seemed  to  conform  with  the  view  of  Charit- 
schkoff, that  the  nonformolite-forming  constituents  (other  than  the 
unsaturated  cyclic  hydrocarbons)  are,  not  only  in  relative  quantity  but 
in  their  viscous  quality,  the  chief  representative  elements  in  the  lubricat- 
ing power,  and  these  include  the  paraffins,  the  naphthenes,  the 
poly-naphthenes,  and  the  olefines.  Engler  discusses  these  results  of  Mar- 
cusson at  some  length,  and  calls  attention  to  the  particular  care  with 
which  the  formolite  reaction  must  be  carried  out  to  insure  accurate 
results,  and  intimates  that  many  of  the  discrepancies  in  the  results 
of  previous  experimenters  may  have  been  due  to  the  overlooking  of 
necessary  precautions  in  the  carrying  out  of  this  reaction,  and  apparently 
expresses  himself  as  satisfied  with  these  latest  results  of  Marcusson, 
based  on  the  use  of  formolite  reaction. 

To  sum  up,  therefore,  I  would  merely  say  that  it  is  desirable  to  con- 
sider this  question  as  not  yet  so  definitely  settled  as  seemed  to  be  expressed 
by  the  statements  of  Doctor  Mabery.  These  studies  of  the  lubricating 
oils  and  the  relation  of  their  composition  to  viscosity  are,  of  course,  of 
the  greatest  interest  and  importance,  but  we  must  not  draw  sharp 
deductions  based  largely  on  a  reaction  that  may  be  carried  out  in  such  a 
way  as  to  give  varying  results. 


520  COMPOSITION   OF   PETROLEUM 

Doctor  Mabery  gives  a  very  interesting  account  of  the  special  class 
of  Ohio  oils  in  which  this  viscosity  is  particularly  developed. 

He  gives  an  outline  of  the  general  methods  of  preparing  commercial 
products  from  petroleum,  covering  the  general  methods  of  refining,  the 
production  of  gasoline  in  increasing  amount  by  cracking  processes, 
although  he  does  not  refer  particularly  to  the  cracking  methods  used  (in 
which  there  is  considerable  variation)  and  takes  up  particularly  the 
matter  of  lubricants  and  their  uses.  Some  notice  might  have  been 
given  of  the  very  large  use  of  clay  filtration,  which  is  an  important  part, 
particularly  in  the  preparation  of  high-grade  lubricants.  Many  of  the 
special  grades  of  lubricants  with  an  exceptional  low  cold  test  and  conse- 
quent availability  for  lubrication,  under  conditions  of  low  temperature, 
are  prepared  exclusively  by  these  methods  of  filtration  with  fuller's  earth 
or  special  grades  of  clay. 

B.  F.  TILLSON,*  Franklin,  N.  J. — The  subject  of  lubrication  received 
considerable  attention  at  the  last  annual  meetings  of  the  American  Society 
of  Mechanical  Engineers  and  of  the  Society  of  Automotive  Engineers, 
and  interest  in  it  seems  to  be  spreading  so  that  there  is  a  tendency  towards 
coordination  of  research  along  the  lines  of  what  should  be  the  properties 
of  a  lubricant  and  a  bearing  in  order  properly  to  utilize  a  lubricant.  The 
opinion  seems  to  be  quite  general  that  oil  grooves  in  bearings  are,  in  the 
main,  detrimental  and,  as  far  as  possible,  should  be  removed;  if  used, 
the  edges  of  the  groove  should  be  tapered  so  as  not  to  form  a  sharp  surface 
that  will  wipe  away  the  oil  from  the  moving  shaft  or  body  that  rests  on 
the  bearing. 

But  I  wonder  whether  there  is  not  the  same  agreement  that,  in  general, 
high  viscosities  are  not  at  all  necessary  properties  of  an  excellent  lubri- 
cant, that  the  lower  the  viscosity  of  the  lubricant  it  is  possible  to  use, 
the  less  is  the  frictional  loss;  that  the  internal  friction  of  the  molecules 
moving  in  oils  of  high  viscosities  is  a  considerable  power  loss? 

In  general,  the  rule  seems  to  be  that  the  viscosity  lessens  as  the  tem- 
perature increases;  but  some  instances  seem  to  indicate  a  reverse  condition. 
I  have  heard  that  waxes  or  paraffins  with  a  low  melting  point  that  have 
been  separated  and  left  in  a  refrigerator  for  some  time  become 
liquid  at  lower  temperatures;  that  some  soaps,  if  left  on  a  window  sill  in 
cold  weather,  change  from  solid  to  liquid  form.  Do  not  such  examples 
indicate  that  research  concerning  the  colloidal  conditions  of  the  elements 
that  form  the  oils  we  are  using  is  greatly  needed? 

Further  research  may  show  that  if  they  do  not  crack  readily  or  deposit 
their  carbons,  oils  of  much  lower  viscosities  than  the  present  practice  in- 
dicates may  be  used  in  both  automotive  and  general  mechanical 
engineering  design. 

*  Min.  Engr.,  New  Jersey  Zinc  Co. 


DISCUSSION  521 

CHARLES  F.  MABERY  (author's  reply  to  discussion). — In  reply  to 
Mr.  Tillson's  question,  as  to  the  relation  of  viscosity  to  the  quality  of 
lubricants,  and  the  influence  of  temperature,  I  think  that  oils  with  the 
lowest  viscosity  to  meet  the  frictional  conditions  should  be  selected. 
The  influence  of  temperature  on  lubricants  does  not  receive  the  attention 
it  should.  The  great  falling  off  in  viscosity  by  even  slight  raise  in  tem- 
perature is  a  direct  measure  of  the  loss  in  power  of  the  lubricant  to  keep 
the  bearing  surfaces  apart. 

In  reply  to  Doctor  Sadtler's  question,  the  lubricant  hydrocarbons 
represented  by  the  formula  CnH2n-2,  are  not  unsaturated  in  the  same 
manner  as  the  acetylenes  or  ethylenes,  and  in  only  one  or  two  instances 
has  the  structure  been  made  out.  But  evidently  a  double  bonded  struc- 
ture is  necessary  to  account  for  the  smaller  number  of  hydrogen 
atoms.  Concerning  the  series  CnH2w-4,  these  hydrocarbons  are  the  least 
volatile  portions  of  petroleum  that  can  be  distilled  without  decomposition. 

Doctor  Sadtler  alludes  to  my  ommission  of  the  use  of  fuller's  earth 
in  refining.  For  some  time  I  have  been  connected  with  the  preparation 
of  low-test  and  high-viscosity  lubricants,  and  have  had  abundant  op- 
portunities to  become  familiar  with  the  usefulness  of  clay  filtration  in 
finishing  these  products. 


522  CARBON   RATIOS    OP   COALS  IN   WEST  VIRGINIA   OIL   FIELDS 


Carbon  Ratios  of  Coals  in  West  Virginia  Oil  Fields 

BY  DAVID  B.  REGBB,*  MORGANTOWN,  W.  VA. 

(New  York  Meeting,  February,  1921) 

THE  value  of  carbon  ratios  in  determining  the  boundaries  of  possible 
oil  deposits  appears  to  have  passed  the  hypothetical  stage.  The  theory 
that  the  ratio  of  fixed  carbon  in  pure  coals  is  an  invariable  index  of  in- 
cipient metamorphism  in  both  surface  and  underground  rocks  and  that 
it  may  be  applied  in  defining  the  limits  of  petroleum,  advanced  by  David 
White,1  has  been  received  with  keen  interest  by  many  petroleum  geolo- 
gists. Detailed  isocarb  maps  have  been  prepared  of  the  Pennsylvanian 
area  of  North  Texas  and  Eastern  Oklahoma  by  M.  L.  Fuller.2  A  similar 
map  of  the  coal-bearing  area  of  West  Virginia  is  given  here.  . 

An  isocarb3  is  a  line  showing  an  equal  fixed-carbon  percentage,  pure 
coal  basis;  the  term  has  been  proposed  by  David  White  to  supersede  a 
less  expressive  nomenclature. 

The  term  carbon  ratio  is  applied  to  the  percentage  of  carbon  in  pure 
coal  after  water  and  ash  have  been  eliminated.  As  a  comparatively 
small  number  of  analyses  have  been  made  on  this  basis,  it  is  usually 
necessary  to  compute  the  ratio  by  dividing  the  fixed  carbon  of  the  proxi- 
mate analysis  by  the  sum  of  the  fixed  carbon  and  volatile  matter  of  the 
same  analysis. 

Many  thousands  of  proximate  analyses  have  been  made  by  the  West 
Virginia  Geological  Survey,  covering  nearly  every  county  in  which  coal 
is  found.  Numerous  others  have  been  made  by  the  U.  S.  Geological 
Survey  and  the  U.  S.  Bureau  of  Mines,  but  as  uniformity  of  results  is 
best  secured  by  adhering  to  one  set  of  analyses,  the  tests  of  the  West 
Virginia  Survey  have  been  exclusively  used. 

*  Assistant  Geologist,  West  Virginia  Geological  Survey. 

1  Some  Relations  in  Origin  between  Coal  and  Petroleum.  Wash.  Acad.  Sci. 
(March  19,  1915)  6,  189-212;  Late  Theories  Regarding  the  Origin  of  Oil.  Bull. 
Geol.  Soc.  Am.  (Sept.  30,  1917)  28,  727-734. 

'Relation  of  Oil  to  Carbon  Ratios  of  Pennsylvanian  Coals  in  North  Texas.  Econ. 
Geol  (November,  1919)  14,  536-542;  Carbon  Ratios  hi  Carboniferous  Coals  of  Okla- 
homa, and  Their  Relation  to  Petroleum.  Econ.  Geol.  (April-May,  1920)  15,  225-235. 

3  The  term  isocarb  has  been  suggested  by  David  White  as  more  accurate  than 
the  word  isovol  originally  used  by  him.  The  termjsovolve,  used  by  Fuller,  appears 
to  be  a  corruption  of  isovol. 


DAVID  B.    REGEB 


523 


In  preparing  the  isocarb  map,  it  has  been  necessary  to  use  analyses 
ranging  from  the  Dunkard  (Permo-Carboniferous)  coals  down  to,  and 
including,  the  Pocahontas  Group  of  the  Pottsville  (Pennsylvanian),  as, 
with  certain  exceptions,  there  is  a  progressive  rise  of  strata  from  the 
Appalachian  geosyncline  southeastward  to  the  Alleghany  Mountains, 
where  the  coals  disappear  above  the  summits.  The  Dunkard  coals, 
being  much  different  in  character  from  those  of  the  Pennsylvanian,  have 
been  used  in  only  one  county  (Tyler).  With  certain  minor  exceptions, 
in  each  county  analyses  from  the  oldest  coal  seams  available  have  been 
employed,  in  order  to  secure  the  nearest  possible  approach  to  under- 


OUTLJNE  MAP 
WEST  VIRGINIA 

SHOWINO 

ISOCARB  LINES 

AMD 

OIL  AND  GAS  AREAS 


ground  conditions.  In  carrying  out  this  rule  two  or  more  seams  have 
been  used  for  different  portions  of  several  counties  where  the  pitch  of  the 
measures  is  large. 

The  table  shows  in  detail  the  various  coals  used  in  preparing  the  m  ap 
few  analyses  of  coals  above  the  Pittsburgh  have  been  employed. 


ISOCARB  MAP 

The  map  shows  the  main  productive  oil  and  gas  fields  of  the  state, 
together  with  isocarb  lines  for  the  coal-bearing  area,  as  plotted  from  the 
preceding  data.  The  dots  with  accompanying  figures  show  the  approxi- 
mate localities  represented  by  each  average  determination.  The  average 
carbon  ratio  falls  below  55  in  parts  of  Roane,  Calhoun,  Gilmer,  Doddridge, 
Lewis,  and  Harrison  counties;  this  area  lies  just  southeast  of  the  Appala- 


524  CARBON  RATIOS   OP  COALS  IN  WEST  VIRGINIA  OIL  FIELDS 

chian  geosyncline,  the  axis  of  which  extends  roughly  from  the  southwest 
corner  of  Pennsylvania  to  the  Kentucky  state  line  in  the  northern  half 
of  Wayne  County. 

It  is  apparent  from  the  map  that  the  main  oil  pools  lie  within  the  limit 
of  isocarb  60,  the  most  notable  exceptions  being  the  Cabin  creek  pool 
of  Kanawha  and  Boone  Counties,  the  southwestern  limit  of  which  is 
not  yet  fully  defined,  and  certain  pools  in  eastern  Kanawha  and  Clay 
Counties.  Oil  also  occurs  in  quantity  in  Brooke  County,  of  the  northern 
panhandle,  where  the  carbon  ratio  is  62.  Recent  we  Is  are  reported 
from  Mingo  County  near  the  point  where  isocarb  65  crosses  the  Kentucky 
line.  Gas  occurs  in  several  localities  on  the  high  side  of  isocarb  65  in 
Raleigh,  Fayette  and  Nicholas  Counties;  it  has  also  been  reported  in  an 
uncompleted  well  in  Northern  Wyoming,  where  the  average  carbon 
ratio  is  69. 

PROBABLE  LIMIT  OF  OIL  AND  GAS 

It  would  seem,  from  the  record  of  numerous  wells  drilled  on  the  high 
side  of  isocarb  60,  that  dry  holes  or  gas  will  be  the  main  result  of  tests 
in  such  territory  (certain  exceptions  have  been  noted  above)  and  that 
wells  drilled  on  the  high  side  of  isocarb  65  can  hope  for  only  occasional 
occurrences  of  gas. 

It  would  seem,  from  the  map,  that  new  production  in  the  western 
portion  of  the  state  is  most  likely  in  Wayne,  Cabell,  Putnam,  Kanawha, 
Mason,  Jackson,  Roane,  Wirt,  Wood,  Marshall  and  Ohio  Counties.  In 
some  of  these,  however,  the  strata  have  not  been  sufficiently  disturbed 
to  afford  gravitational  segregation  of  oil,  gas,  and  water,  and  in  various 
regions  of  these  counties  where  favorable  synclines  occur  the  sands  are 
known  to  be  saturated  with  water,  contrary  to  the  general  rule  through- 
out the  state.  In  spite  of  these  two  unfavorable  features,  the  writer  be- 
lieves that  several  new  pools  will  be  developed  in  some  of  these  counties. 

In  the  central  belt,  certain  undeveloped  portions  of  Nicholas,  Braxton, 
Lewis,  Upshur,  B arbour,  and  Marion  Counties  lie  on  the  low  side  of 
isocarb  60,  so  that  production  may  reasonably  be  expected  from  some  of 
these.  As  the  structure  of  this  region  is  largely  monoclinal,  the  main  hope 
of  oil  will  depend  on  terraces.  Inasmuch  as  there  is  a  rapid  southeast- 
ward expansion  of  the  Pottsville,  Mauch  Chunk,  and  Greenbrier  Series 
structure  maps  based  on  surface  strata  do  not  fully  reveal  such  terraces 
and  their  location  cannot  be  made  until  sufficient  holes  have  been  drilled 
to  afford  the  necessary  subsurface  data. 

COMPARISON  WITH  OTHER  STATES 

The  researches  of  M.  L.  Fuller  show  that  in  both  Oklahoma  and  north- 
ern Texas  the  main  producing  fields  lie  on  the  low  side  of  isocarb  55, 


DAVID  B.    EEGER 


525 


Table  of  Coal  Analyses  and  Carbon  Ratios 


County 

Locality 

Coal  Seam 
and  Group 

Number 
of 
Analyses 

Volatile 
Matter, 
Aver- 

aS 

Cent. 

Fixed 
Carbon, 
Aver- 

K 

Cent. 

F.  C. 

F.  C.  -f  V.  M. 

Nearest 
Per 
Cent. 

Hancock  

East 
West 
East 
West 
East 
West 
North 
South 

Northwest 
Southeast 
Northwest 
Southeast 

West 
East 

West 
East 
West 
East 
West 
East 
North 
Central 
South 
North 
South 
North 
South 
Northwest 
Southeast 
West 
East 
West 
East 
North 
South 
Northwest 

Southeast 
Central 
North 
Central 
South 
West 

West 

j.  Kittanning  (Ca) 
Pittsburgh  (Cm) 
Pittsburgh  (Cm) 
^ittsburgh  (Cm) 
Jniontown  (Cm) 
Washington  (Cd) 

Pittsburgh  (Cm) 
Little  Pittsburgh 
(Com) 
No.  2  Gas  (Ck) 
No.  2  Gas  (Ck) 
Pittsburgh  (Cm) 
Brush  Creek  (Ccm) 
Bakerstown  (Ccm) 
Pittsburgh  (Cm) 
[Jniontown  (Cm) 
L.  Kittanning  (Ca) 
Pittsburgh  (Cm) 
L.  Kittanning  (Ca) 
Pittsburgh  (Cm) 
Harlem  (Ccm) 
Pittsburgh  (Cm) 
Pittsburgh  (Cm) 
L.  Kittanning  (Ca) 
Pittsburgh  (Cm) 
Pittsburgh  (Cm) 
Coalburg  (Ck) 
Pittsburgh  (Cm) 
Eagle  (Ck) 
No.  5  Block  (Ca) 
Eagle  (Ck) 
Campbell  Creek  (Ck) 
Eagle  (Ck) 
Eagle  (Ck) 
No.  3  Pocohantas 
(Cp) 
Gilbert  (Ck) 
Sewell  (Cnr) 
Eagle  (Ck) 
Fire  Creek  (Cnr) 
Eagle  (Ck) 
Fire  Creek  (Cnr) 
L.  Kittanning  (Ca) 
Eagle  (Ck) 
Sewell  (Cnr) 
Pittsburgh  (Cm) 
L.  Kittanning  (Ca) 
Redstone  (Cm) 
L.  Kittanning  (Ca) 
Pittsburgh  (Cm) 
L.  Kittanning  (Ca) 
Pittsburgh  (Cm) 
L.  Kittanning  (Ca) 
U.  Freeport  (Ca) 
L.  Kittanning  (Ca) 
U.  Freeport  (Ca) 
Sewell  (Cnr) 
M.   &  L.  Kittanning 
(Ca) 
Sewell  (Cnr) 
Sewell  (Cnr) 
L.  Kittanning  (Ca) 
Eagle  (Ck) 
Sewell  (Cnr) 
Sewell  (Cnr) 

No.  3  Pocahontas 

Gilbert  (Ck) 
U.  Freeport  (Ca) 
U.  Freeport  (Ca) 

3 
15 
6 

7 
1 
3 

5 
1 

3 
4 
8 
2 
43 
5 
56 
2 
8 
21 
2 
6 
14 
7 
13 
6 
9 
5 
3 
14 

4 
5 
23 
5 
16 
18 
17 
24 
29 
7 
3 
12 
5 
10 
18 
10 
5 
43 
12 
6 
1 
8 

15 
9 
7 
6 
17 
1 

17 

1 

1 
4 

37.91 
34.20 
35.92 
38.40 
37.07 
34.27 

38.79 

39.82 
40.02 
39.29 
38.53 
37.20 
33.43 
37.45 
39.36 
30.47 
36.47 
33.90 
36.62 
35.81 
38.24 
41.92 
34.52 
41.84 
34.99 
34.05 
40.06 
31.22 
37.31 
34.98 
34.92 
30.45 
31.29 
17.90 

27.84 
23.31 
29.29 
20.56 
28.25 
19.29 
35.33 
33.43 
29.10 
39.68 
37.02 
38.36 
35.36 
36.90 
30.77 
37.01 
29.90 
27.25 
29.49 
22.05 
24.81 
32  14 

30.35 
26.59 
32.47 
35.45 
30.07 
26.96 

19.85 

29.73 
18.46 
15.50 

53.00 
56.08 
55.17 
50.97 
53.07 
47.92 

49.33 

46.83 
55.42 
55.81 
51.40 
44.12 
42.75 
52.50 
45.29 
57.53 
54.86 
49.83 
55.73 
49.70 
53.53 
51.08 
53.41 
49.49 
56.95 
56.10 
51.48 
63.09 
55.73 
57.55 
59.27 
63.06 
62.44 
76.13 

63.61 
72.76 
65.02 
77.37 
66.61 
75.42 
53.97 
59.74 
65.73 
51.78 
56.02 
54.35 
51.78 
55.63 
56.85 
55.19 
58.96 
62.52 
59.42 
70.20 
68.18 
55.63 

61.80 
60.84 
54.08 
54.04 
62.08 
66.77 

66.48 

56.21 
68.64 
73.46 

58 
62 
60 

57 
59 

58 

56 

54 
58 
58 
57 
54 
56 
57 
53 
65 
60 
59 
60 
58 
58 
55 
60 
54 
61 
62 
56 
66 
59 
61 
62 
67 
66 
80 

69 
75 
70 
79 
70 
79 
60 
64 
69 
56 
60 
58 
59 
60 
64      :,,, 
59 
66 
69 
66 
76 
73 
63 

67 
69 
62 
60 
67 
71 

77 

65 

78 
82 

Brooke  
Ohio  

Marshall  
Wetzel  
Tyler            

Pleasants  
Wood  

Cabell            

Wayne       

Putnam       

Wirt            

Ritchie             .... 

Doddridge   

Monongalia.  ...... 
Marion             .... 

Harrison          .... 

Lewis           

Gilmer  

Clay               

Kanawha  
Boone               .... 

Logan               .... 

McDowell 

Raleigh 

Fayette  
Nicholas  

Braxton  

Taylor              .  .  . 

Preston        

Tucker     

Randolph  
Webster  

Greenbrier  

Summers  
Mercer  

Pocahontas  
Grant 

Mineral  

NOTE. — Group  abbreviations  are  as  follows:  Cd-Dunkard  (Permo-Carboniferous) ;  Cm,  Monongahela- 
Ccm,  Conemaugh;  Ca,  Allegheny;  Ck,  Kanawha;  Cnr.  New  River;  and  Cp,  Pocahontas  (last  six 
Pennsylvanian). 


526  CARBON  RATIOS  OF  COALS  IN  WEST  VIRGINIA  OIL  FIELDS 

there  being  important  exceptions  in  the  former  and  smaller  deviations 
in  the  latter  state.  In  neither  state  are  oil  pools  of  importance  noted 
above  isocarb  60.  In  West  Virginia,  however,  many  of  the  large  pools 
lie  above  isocarb  55,  and  some  large  pools  occur  above  isocarb  60,  while 
gas  extends  to  still  higher  limits.  The  occurrence  of  oil  at  high  carbon 
levels  in  the  latter  state  is  reflected  by  its  quality,  since  it  is  generally 
of  higher  Baume*  gravity  than  those  of  the  other  states,  and  commands  a 
higher  market  price,  indicating  that  the  process  of  natural  distillation  is 
more  nearly  complete. 

DISCUSSION 

JOSEPH  T.  SINGEWALD,  JR.,*  Baltimore,  Md. — The  utility  of  geology 
in  locating  and  developing  oil  fields  is  as  much  negative  as  it  is  positive; 
it  is  just  as  important  and  valuable  to  eliminate  large  areas  in  which  you 
cannot  expect  to  find  oil  or  gas,  as  it  is  to  select  certain  smaller  and 
restricted  areas  in  which  you  may  expect  to  find  it.  The  processes  are 
really  the  same.  If  the  isocarbs  are  a  criterion  for  eliminating  large 
areas  as  not  being  likely  fields  of  oil  and  gas,  they  are  of  immense  practical 
value.  We  cannot  always  apply  this  criterion  as  we  do  not  always  have 
coal  seams  in  an  oil  and  gas  region.  Although  first  announced  in  1915, 
for  the  Appalachian  field,  this  criterion  has  since  been  tested  only  in 
Oklahoma  and  northern  Texas.  The  Pennsylvania  State  Survey  is 
now  making  an  isocarb  map  of  that  state.  West  Virginia  offers  the  best 
opportunity  for  testing  it,  in  that  we  have  many  more  analyses  of  its 
coals  than  those  of  other  states.  The  map  of  Mr.  Reger  shows  a  distinct 
line  running  northeast  and  southwest,  southeast  of  which  there  are  no 
oil  or  gas  fields.  In  Maryland  we  now  have  an  opportunity  to  test  this 
method.  The  western  boundary  of  the  state  lies  to  the  east  of  the  line 
on  Mr.  Reger's  map.  They  are  drilling  along  the  Potomac  River  and 
are  about  to  commence  drilling  in  Garrett  County,  the  extreme  western 
part  of  the  state.  Stratigraphically,  one  might  consider  conditions  as 
favorable  there  as  in  West  Virginia  and,  at  first  sight,  structurally  they 
might  be  considered  more  favorable,  in  that  the  structure  is  more  pro- 
nounced. The  folding,  thinking  of  it  only  in  terms  of  the  angles  of  dip, 
would  appear  no  more  intense  than  in  some  of  the  western  states.  So, 
if  the  degree  of  metamorphism  is  not  taken  into  consideration,  we  might 
be  inclined  to  recommend  drilling  in  Garrett  County.  But  if  the  degree 
of  metamorphism  is  tested  by  the  isocarbs  we  ought  to  say  not  to  drill. 
As  yet,  however,  the  theory  has  been  tested  in  so  few  places  that  we 
cannot  say  "Do  not  drill,"  with  absolute  confidence. 

So  much  for  the  grosser  application  of  the  isocarbs  in  ruling  out 
certain  areas  as  not  being  possible  localities  for  the  occurrence  of  oil  and 

*  Associate  Professor,  Economic  Geology,  Johns  Hopkins  University. 


DISCUSSION  527 

gas.  It  seems  to  me  that  the  theory  might  also  be  applied  to  great 
advantage  in  more  detail.  Take  the  case  of  West  Virginia,  where  we 
have  a  great  many  analyses  in  individual  counties.  If  we  draw  in  greater 
detail  on  a  larger  scale,  the  curves  of  isocarbs  and  compare  the  irregu- 
larities in  those  curves  with  the  physical  and  chemical  character  of  the 
oil,  the  theory  may  give  us  valuable  conclusions  as  to  the  geologic  his- 
tory of  the  oil  itself. 

We  know  that  a  certain  oil  has  certain  physical  and  chemical  prop- 
erties, but  we  do  not  know  to  what  extent  that  oil  has  its  own 
peculiar  properties  on  account  of  the  original  composition  of  the  material 
from  which  it  has  been  derived,  and  to  what  extent  it  has  those  porp- 
erties  on  account  of  the  geological  history  through  which  it  has  gone. 
The  details  of  the  isocarbs  would  appear  to  have  within  them  the  pos- 
sibility of  throwing  light  on  that  subject.  It  is  a  line  of  investigation 
worthy  of  more  attention. 


528  PRODUCTION,  TRANSPORTATION  &  TAXATION  OF  MEXICAN  PETROLEUMS 


General  Notes  on  the  Production,  Marine  Transportation 
and  Taxation  of  Mexican  Petroleums 

BY  VALENTIN  R.  GARFIAS,*  NEW  YORK,  N.  Y. 

(New  York  Meeting,  February,  1921) 

PRODUCTION  AND  MARINE  TRANSPORTATION 

ALTHOUGH  the  work  on  which  this  paper  is  based  was  carried  on  by 
the  writer  as  Special  Commissioner  of  the  Petroleum  Department  of  the 
Mexican  Government,  the  opinions  expressed  are  only  his  personal  views 
for  which  the  Mexican  Government  can  in  no  way  be  held  responsible. 
Notwithstanding  that  the  appointment  covers  all  phases  of  the  so-called 
petroleum  question,  as  the  one  question  of  immediate  importance  was 
that  relating  to  taxation,  it  was  decided  to  devote  all  the  time  to  this 
phase  of  the  work. 

The  present  report  has  been  divided  into  two  closely  related  parts, 
the  first  dealing  with  the  production  and  marine  transportation  of  Mexi- 
can petroleum,  and  the  second,  with  the  Mexican  taxation  on  petroleum 
and  its  products. 

The  writer  wishes  to  acknowledge  the  loyal  cooperation  rendered  by 
Mr.  M.  C.  Ehlen,  who  had  charge  of  the  statistical  work,  and  by  Miss 
S.  Stern  and  Messrs.  E.  P.  Heiles  and  J.  E.  Morrissey. 

The  aim  throughout  the  work  has  been  to  pave  the  way  for  a  thor- 
ough understanding  between  the  Mexican  Government  and  the  oil 
operators  and  to  present  a  true  and  clear  statement  of  facts  relating  to  the 
questions  at  issue. 

MEXICAN  OIL  FIELDS  DEVELOPMENT 

The  salient  features  in  the  development  of  the  Mexican  oil  fields  may 
be  summarized  as  follows: 

1901.  First  commercially  productive  well  in  Ebano  field. 

1902.  Tehuantepec  field  came  in;  Diaz  Government  granted  conces- 
sion to  Pearson  &  Son  on  practically  all  Federal  lands  along  the  Gulf  of 
Mexico. 

1907.  First  producing  well  in  the  Furbero  field. 

1908.  Dos  Bocas  well  caught  fire,  advertising  tremendous  produc- 
tivity of  Southern  oil  fields  of  Mexico. 

*  Manager  of  Foreign  Oil  Department,  Henry  L.  Doherty  &  Co. 


VALENTIN  B.   GARFIAS 


529 


1909.  Tanhuijo  field,  discovery  well. 

1910.  Discovery  of  oil  in  Juan  Casiano,  Potrero,  Panuco,  and  Topila, 
placed  Mexico  as  a  leader  in  oil  production. 

1911.  First  shipment  of  Mexican  oil  made  to  United  States,  on 
May  25. 

1913.    Alamo  field  of  Penn-Mex  Co.  discovered. 
1917.     New  Constitution  of  Mexico,  establishing  national  ownership 
of  subsoil  rights  was  enacted,  May  1. 

1917.  Cerro  Azul  field  discovered. 

1918.  Tepetate  and  Naranjos  fields  came  in. 

1919.  Casiano,  Tepetate,  and  Potrero  fields  went  to  water. 

1920.  Chinampa  field  showed  water  in  August. 

1920.  Zacamixtle  field  came  in  on  Oct.  8. 

1921.  Naranjos  field  showed  water,  Feb. 

Table  2  shows  the  holding  companies  and  subsidiaries  at  present 
operating  in  the  fields  and  marketing  Mexican  oils. 

TABLE  1. — Relative  Daily  Production  per  Well  in  Mexican  and  American 

Oil  Fields 


Field  and  State 

Producing 
Wells 

Drilling 
Wells 

Well 
Locations 

Abandoned 
Wells 

Production 

Daily 

Well 
Daily 

Mid-continent. 
Oklahoma    

47,574 
9,693 
2,694 
13,708 
3,252 
15,692 

13,975 
512 
8,796 

71,101 
17,302 
14,178 
868 
9,357 

1,691 
2,814 
488 
368 
462 
49 

66 
55 
932 

246 
252 
116 
381 
422 

594 
1,159 
333 
113 

184 
4 

10 
7 
13 

115 
147 
75 
181 
66 

[n  1913  «  7163  wells, 
[n  1914  «  5607  wells, 
[n  1915  =  6029  wells, 
[n  1916  =  6017  wells 
[n  1917  =  6542  wells 

302,567 
192,533 
103,867 
117,166 
68,067 
31,033 

4,467 
2,666 
25,633 

24,467 
23,067 
15.433 
54,767 
273,000 

6.40 
19.90 
38.50 
8.50 
20.90 
1.90 

0.32 
5.20 
2.90 

0.34 
1.30 
1.10 
63.00 
29.50 

North  and  Central  Texas  

Gulf  Coast    

Illinois    

Lima—  Indiana  . 
Lima  

Appalachian. 
Pennsylvania  and  New  York. 
West  Virginia                 

South,  East  and  Central  Ohio 
Rocky  Mountain              

California        ...        

Total          

228,702 

8,342 

3,001 

1,240,633 

5.4 

Mexico  

(a)  61 
(6)80 
(6)  249 

26 

12 

567 

237,884 
296,305 
296,305 

3900.00 
3710.00 
1190.00 

1.  The  figures  relating  to  the  American  fields  are  those  for  the  month  of  June,  1920 ,  published  by 
the  U.  8.  Geological  Survey. 

2.  The  wells  abandoned  in  the  American  fields  are  listed  by  years,  as  given  by  the  U.  S.  Geological 
Survey.     The  figures  (567)  for  wells  abandoned  in  the  Mexican  fields  include  the  total  abandonments 
to  date. 

3.  The  well  statistics  for  the  Mexican  fields  (a)  refer  to  conditions  on  June,  1919,  as  given  by  Boletin 
del  Petroleo:   b)  refer  to  conditions  during  December,  1919,  as  given  in  Oil  and  Gas  Journal.     The 
number  of  actually  producing  wells  (80)  during  December.  1919  is  estimated. 
VOL.  LXV. — 34. 


530   PRODUCTION,  TRANSPORTATION  &  TAXATION  OP  MEXICAN  PETROLEUMS 


TABLE   2. — Foreign  Companiesy  Producing  and  Marketing,  at  Present 

Operating  in  Mexico 


Atlantic,  Gulf  and  West  Indies  S.  S.  Co. 

Cia  Petrolera  de  Tepetate. 
Agwi  Pipeline  Co. 
Agwi  Refining  Co. 
Agwi  Terminal  Co. 

Cities  Service  Co. 

Cia  de  Gas  y  Combustible  Imperio,  S.  A. 
Cia  Terminal  Imperio,  S.  A. 
Cia  Emmex  de  Petroleo  y  Gas,  S.  A. 
Empire  Transportation  and  Oil  Corpn. 

Gulf  Coast  Corpn. 

Lagunita  Oil  Co. 

National  Petroleum  Corpn. 

Southern  Fuel  &  Refining  Co. 

Tampascas  Oil  Co. 

Cia  Mezicana  de  Oleoductos  Imperio,  S.  A 

Compania  Terminal  Union. 

Hispano  Mejicana  Oil  Co. 
Hispano  Cubana  Oil  Co. 

East  Coast  Oil  Co.,  S.  A. 
Southern  Pacific  Railroad. 

General  Petroleum  Company  of  California. 
Continental  Mexican  Oil  Co. 

Gulf  Oil  Corpn. 

Mexican  Gulf  Oil  Corpn. 

Island  Oil  and  Transport  Corpn. 

Antillian  Corpn. 

Capuchinas  Oil  Co. 

Colombia  Petroleum  Syndicate,  Ltd. 

Cia  Metropolitan  de  Oleoductos,  S.  A. 

Cia  Mexicana  de  Petroleo  La  Libertad,  S.  A. 

Cia  Petrolera  Nayarit,  S.  A. 

Esfuerzo  Tampiqueno,  S.  A. 

Island  Refining  Corpn. 

Metropolitan  Petroleum  Corpn. 

Interocean  Oil  Co. 

U.  S.  Asphalt  Refining  Co. 

Mexican  Crude  Oil  &  Asphalt  Product  Co. 

Mexican  Petroleum  Co.,  Ltd. 
Pan-American  Petroleum  &  Transport  Corpn. 
Caloric  Co. 

Huaateca  Petroleum  Co. 

Cia  Naviera  Transportadora  de  Petroleo,  8.  A. 
Tamiahua  Petroleum  Co. 
Tuxpam  Petroleum  Co. 
Chiconcillo  Petroleum  Co. 
Doheny  &  Bridge. 

National  Oil  Co. 

National  Shipbuilding  Co. 

Comalea  Oil  Co. 

Cia  Exploradora  del  Petroleo,  S.  A. 


New  England  Oil  Corpn. 
Cochrane,  Harper  and  Co. 
Canada  Mexico  Oil  Co. 
France  and  Canada  Oil  Transport  Co. 
New  England  Exploration  Co. 
New  England  Oil  Refining  Co. 

(See  also  Magnolia  Petroleum  Co.) 
Pierce  Oil  Corpn. 

Cia  Mexicana  de  Combustibles,  S.  A. 
Anglo-Dutch  Interests. 
La  Corona  Petroleum  Co. 

Chijoles  Oil,  Ltd. 

Cia  Mexicana  de  Petroleo  La  Corona. 

Tampico  Panuco  Petroleum  Co. 
Mexican  Eagle  Oil  Co.,  (Aguila). 

Eagle  Oil  Transport  Co.,  Ltd. 

Oilfields  of  Mexico,  S.  A. 
Scottish  American  Oil  and  Transport  Corpn. 

Southern  Oil  &  Transport  Corpn. 

Fuel  Oil  Distribution  Corpn. 

Tampico  Navigation  Co. 

Tampico  Shipbuilding  Corpn. 

Tal  Vez  Oil  Co. 

Scottish  Mexican  Oil  Co. 
Sinclair  Consolidated  Oil  Corpn. 
Sinclair  Gulf  Corpn. 

Sinclair  Mexican  Petroleum  Co. 

Freeport  and  Tampico  Fuel  Oil  Corpn. 

Freeport  and  Mexican  Fuel  Oil  Corpn. 

Freeport  and   Tampico   Fuel    Oil    Transp. 

Corpn. 
Mexican  Seaboard  Oil  Co. 

International  Petroleum  Co. 
Standard  Oil  Interests. 
Atlantic  Lobos  Oil  Co. 

Port  Lobos  Petroleum  Corpn. 

Cortex  Oil  Corpn. 

Atlantic  Petroleum  Producing  &  Refining  Co. 
of  Mexico,  S.  A. 

Atlantic  Oil  Co. 

Panuco  Boston  Oil  Co. 

Producers  Terminal  Corpn. 
Magnolia  Petroleum  Co. 

Azteca  Petroleum  Co. 

Cia  Inversiones  de  Aztlan,  S.  A. 

New  England  Fuel  Oil  Corpn. 
Compania  Transcontinental  de  Petroleo,  S.  A. 

Panuco  Excelsior  Oil  Co. 

Vera  Cru*  Mexican  Oil  Co. 
Penn-Mex  Fuel  Co. 
Texas  Company  of  Mexico. 

Panuco  Transportation  Company  of  Mexico. 
Tex-Mex  Oil  Co. 
Tidewater  Petroleum  Co. 

Tide-Mex  Oil  Co. 
Union  Oil  Company  of  California. 
Otontepeo  Petroleum  Co. 
California  Investment  Co. 


VALENTIN  B.    GAEPIAS  531 

TABLE  3.  —  Comparison  of  Mexican  and  American  Standards  for  Measuring 
Petroleum  and  Its  Products 

Volume  Relations 
1  U.  S.  barrel  =    42  .  00  U.  S.  gal.  1  U.  S.  gallon  =    231  .  00  cu.  in. 

=      5.  6145  cu.  ft.  =        0.  13368  cu.  ft. 

=  158.  985  U.  =        3.  7853  U. 

=      0.158985  cu.  m.  =        0.0037853  cu.  m. 

1  cubic  foot  =      7.4807  U.  S.  gal.         1  cubic  meter  =  1000.00  li. 

=      0.17811U.  S.  bbl.  =      35.  31445  cu.  ft. 

=    28  .  317  li.  =    264  .  1775  U.  S.  gal. 

6.  2899  U.  S.  bbl. 
1  liter  =  0.  03531  cu.  ft. 

=  0.  26418  U.  S.  gal. 
=  0.0062899  U.S.  bbl. 

The  American  standard  weight  of  water  is  taken  with  water  at  60°  F.;  the  Mexi- 
can standard,  with  water  at  4°  C.  (39.2°  F.). 

Volume  Weight  Relations  of  Water  at  60°  F. 
8.  32823  Ib.  per  U.  S.  gal. 
349.78566  Ib.  per  U.  S.  bbl. 
Metric  ton  (2204.622  Ib.)  per  6.3028  U.  S.  bbl. 
Long  ton  (2240  Ib.)  per  6.4039  U.  S.  bbl. 

The  specific  gravities  of  oils  are  expressed  in  the  Mexican  and  American  standards 
as  follows  : 

Mexican  Standard 
Weight  of  volume  of  oil  at  20°  C. 
Spec   ic  gravity  =  Weight  of  same  volume  ofVater  at  4°  C. 

American  Standard 
Weight  of  volume  of  oil  at  60°  F. 
ic  gravity  -  Weight  of  same  voiume  of  water  at  60°  p. 

Density  is  the  weight  per  unit  volume. 

The  formulas  for  converting  Baume*  degrees  into  specific  gravity  at  60°/60°  F. 
and  vice  versa,  are  as  follows  : 

Baume-  degrees  =  Sp.  Gr.  x*  6o°/60°  F.  ~  13° 
Specific  gravity 


To  convert  specific  gravity  of  oil  from  the  American  to  the  Mexican  standard 
multiply  the  specific  gravity  as  shown  on  the  American  hydrometer  by  0.001061 
and  subtract  the  result  from  the  American  hydrometer  reading;  vice  versa,  to  correct 
from  Mexican  into  American  reading,  multiply  the  specific  gravity  shown  by  the 
Mexican  hydrometer  by  0.001062,  and  add  the  result  to  the  Mexican  hydrometer 
reading. 

The  coefficient  of  expansion  per  degree  Fahrenheit  for  oils  varies  with  the  specific 
gravity  (60°/60°  F.)  as  follows: 
0  .  67  specific  gravity  .........  0  .  000728        0  .  87  specific  gravity  .........  0  .  000419 

0  .  72  specific  gravity  .........  0  .  000627        0  .  91  specific  gravity  ......  ...  0  .  000392 

0  .  77  specific  gravity  .....  ____  0  .  000540        0  .  96  specific  gravity  .........  0  .  000368 

0  .  82  specific  gravity  .........  0  .  000470         1  .  00  specific  gravity  .........  0  .  000356 

To  ascertain  the  number  of  U.  S.  barrels  of  oil  at  60°  F.  in  1  metric  ton  of  2204.622 
Ib.,  divide  the  specific  gravity  at  60°  F.  into  6.3028;  for  barrels  per  long  ton,  divide 
specific  gravity  at  60°  F.  into  6.4039. 


532   PRODUCTION,  TRANSPORTATION  &  TAXATION  OF  MEXICAN  PETROLEUMS 


TABLE  4. — Relation  Between  World's  and  United  States1  Petroleum  Pro- 
duction and  Mexican  Production  and  Exports  in  Barrels  of 
42  U.  S.  Gallons 


Year 

World's 
Production^ 

United  States 
Production 

Mexican  Production 

Mexican  Exports 

Total 

Per 
Cent, 
of 
World 

Totalt 

Per 

cent 
of 
World 

Totalt 

To  U.  S.  A.t 

Per 
Cent, 
to 
U.  S.  A. 

1901 

167,434,434 

69,389,194 

41.4 

10,345 

0.006 

1902 

182,006,076 

88,766,916 

38.7 

40,200 

0.02 

1903 

194,879,669 

100,461,337 

51.3 

75,375 

0.04 

1904 

218,204,391 

117,080,960 

53.6 

125,625 

0.06 

1905 

215,292,167 

134,717,580 

62.6 

251,250 

0.12 

1906 

213,415,360 

126,493,936 

59.2 

502,500 

0.23 

1907 

264,245,419 

166,095,335 

62.8 

1,005,000 

0.38 

1908 

285,552,746 

178,527,355 

62.5 

3,932,900 

1.38 

1909 

298,616,405 

183,170,874 

61.4 

2,713,500 

0.91 

1910 

327,937,629 

209,557,248 

63.9 

3,634,080 

1.11 

1911 

344,174,355 

220,449,391 

64.1 

12,552,798 

3.65 

893,709 

1912 

352,446,598 

222,935,044 

65.0 

16,558,215 

4.70 

7,627,795 

7,383,229 

96.9 

1913 

383,547,399 

248,446,230 

64.8 

25,696,291 

6.70 

20,915,928 

17,809,058 

85.2 

1914 

403,745,342 

265,762,535 

65.8 

26,235,403 

6.50 

22,880,530 

16,245,975 

71.0 

1915 

427,740,129 

281,104,104 

65.8 

32,910,508 

7.70 

24,279,375 

17,478,472 

72.0 

1916 

461,493,226 

300,767,158 

65.0 

40,545,712 

8.79 

26,746,432 

20,125,657 

75.2 

1917 

506,702,902 

335,315,601 

66.2 

55,292,770 

10.91 

42,545,843 

29,933,516 

70.4 

1918 

514,538,716 

355,927,716 

69.2 

63,828,000 

12.40 

51,768,010 

40,819,870* 

78.9 

1919 

557,500,000° 

377,719,000 

67.8 

92,402,055* 

16.56 

77,703,289* 

57,618,589* 

74.1 

1920 

660,000,000 

443,402,000 

67.0      185,000,000 

28.0 

147,204,000 

112,374,000 

76.0 

*  Oil  and  Gas  Journal. 

t  Boletin  del  Petroleo  (Mexico  City). 


t  U.  S.  Geological  Survey. 
0  Estimated. 


TABLE  5. — Summary  of  Mexican  Oil  Production,  Exports,  Stocks,  and 

Domestic  and  Field  Consumption  During  1917  to  1920  in 

Barrels  of  42  U.  S.  Gallons 


1917 

1918 

1919 

1920 

Exports  . 

42  545,843 

51,780,479 

75,812,760 

147,204,000* 

Bunker  fuel  

12,746,927 

2,336,768 

1,890,529 

Domestic  consumption 

9,218,491 

14,098,766 

33,000,000 

Loss  in  refining  

492,588 

600,000 

Total  net  production 

55  292,770 

63,828,326 

92,402,055 

180,204,000* 

Field  consumption  and  losses 
Oil  in  steel  storage 

10  000,000 

4,781,509 
14,526,559 

5,000,000 
12,528,518 

13,000,000 

NOTE.— 1917-1918  figures 
from  the  Oil  and  Gas  Journal. 
Petroleum  Department.  1919 


taken  from  Boletin  del  Petroleo.     1919  figures  taken 
Field  consumption  for  1918  estimated  by  Mexican 
figures  also  estimated. 


Estimated. 


VALENTIN   R.    GARFIAS 


533 


TABLE  6. — Mexican    Oil    Exports  from  Tampico,   Tuxpan,  and   Port 
Lobos  to  Destinations  in  Barrels  of  42  U.  S.  Gallons 


1917 

1918 

1919 

1920 

Exports 

Per 

Cent. 

Exports 

Per 
Cent. 

Exports 

Per 
Cent. 

Exports 

Per 

Cent. 

32,537,821 
13,516,337 

70.6 
29.4 

37,176,008 
15,849,998 
3,739,390 

65.5 
27.9 
6.6 

44,092,135 
17,166,714 
20,070,993 

55.0 
21.0 
24.0 

89,909,213 
18,786,904 
44,579,183 

58.7 
12.2 
29.1 

Port  Lobos 

46,054,158 

100.0 

56,765,396 

100.0 

81,329,842 

100.0 

153,275,300 

100.0 

Destination: 
United  States  

35,386,242 
630,579 
4,801,536 
535,367 

679,157 
49,836 

3,971,441 

76.7 
1.38 
10.60 
1.16 

1.48 
0.11 

8.60 

40,819,870 
681,177 
5,557,827 
377,394 
885,483 
2,600,806 

4,689,774 
1,153,065 

71.9 
1.2 
9.7 
0.6 
1.6 
4.6 

8.3 
2.1 

57,618,589 
2,558,496 
6,642,985 
553,692 
1,964,282 
3,054,357 
239,985 
277,591 
110,509 
66,767 

95,794 
116,716 

72,504 
5,996,982 
1,960,593 

70.8 
3.1 
8.2 
0.7 
2.4 
3.8 
0.3 
0.3 
0.1 
0.1 

0.1 
0.2 

0.1 
7.4 
2.4 

112,373,795 
2,010,958 
13,087,007 
593,252 
5,754,903 
5,493,533 
1,101,448 
579,496 
107,341 
159,130 
144,624 
41,952 
58,433 
463,179 
60,538 
101,729 
132,630 
6,070,439 
4,895,265 
45,648 

73.3 
1.3 
8.5 
0.4 
3.8 
3.7 
0.7 
0.4 
0.1 
0.1 
0.1 
0.0 
0.0 
0.3 

o.o 

0.1 
0.1 
3.9 
3.2 

0.0 

Canada  

Central  America  
West  Indies  

Great  Britain  

Netherlands 

France 

Portugal 

Mediterranean  Ports. 
Gibraltar 

Malta            ...    . 

Tunis               

Eeynt 

Algiers             .  .    .    . 

Italy       

Suez               

Mexican  coastwise  .-. 
Bunker  fuel       .  .       . 

Local  deliveries  

46,054,158 

100.00 

56,765,396 

100.0 

81,329,842 

100.0 

153,275,300 

100.0 

TABLE  7. — Mexican  Oil  Exports  to  United  States  Harbors  from  January 
1917.    In  Barrels  of  42  U.  S.  Gallons 


1917 

1918 

1919 

1920 

Exports 

Per 
Cent. 

Exports 

Per 

Cent. 

Exports 

Per 
Cent. 

Exports 

Per 
Cent. 

Texas  Ports  

9,023,492 
7,254,180 
3,680,169 
13,552,930 
1,875,471 

25.5 
20.5 
10.4 
38.3 
5.3 

9,878,409 
8,082,334 
2,571,652 
17,144,345 
3,143,130 

24.2 
19.8 
6.3 
42.0 

7.7 

15,787,493 
8,181,840 
1,959,032 
26,965,499 
3,975,683 
749,042 

' 
27.4 
14.2 
3.4 
46.8 
6.9 
1.3 

30,941,986 
14,824,281 
6,087,332 
48,626,183 
11,098,771 
795,242 

27.5 
13.1 
5.4 
43.3 
9.9 
0.8 

New  Orleans  

Florida  Ports  

New  York  

New  England  Ports  
California             • 

Total  to  United  States 

35,386,242 

100.0 

40,819,870 

100.0 

57,618,589 

100.0 

112,373,795 

100.0 

534   PRODUCTION,  TRANSPORTATION  &  TAXATION  OF  MEXICAN  PETROLEUMS 


TABLE  8. — Mexican  Oil  Exports  by  Companies  from  January,  1917, 
In  Barrels  of  42  U.  S.  Gallons 


Company 

1917 

1918 

1919 

1920 

Standard  Oil  Group 
Standard  Oil  Co.  of  New  York    | 
Standard  Oil  Co.  of  New  Jersey  [  

5,035,774 

7,645,671 

6  970,927 

21,502,886 

Transcontinental  Petroleum  Co.  J 
Penn-Mez  Fuel  Co 

3  451  226 

7  007  833 

8  495  047 

3  176  963 

Cortez  Oil  Corpn  

1  935,360 

9,096,435 

7,960,959 

48,777 

385,996 

Magnolia  Petroleum  Co.  (New  England).. 
Mexican  Petroleum  Co. 
Huasteca  Petroleum  Co  

12,236,388 

11,708,109 

12,651,974 

29,280,421 

Royal  Dutch  Shell  and  British  Interests 
Mexican  Eagle  Oil  Co.  (El  Aguila)  

8,567,299 

8,583,258 

12,570,492 

17,266,692 

La  Corona  Petroleum  Corpn  

524,626 

2,895,587 

Tal  Vez  Oil  Co  

24,368 

98,896 

398,889 

504,993 

The  Texas  Co  

1,955,146 

1,256,128 

6,814,084 

12,355,082 

Sinclair  Consolidated  Oil  Co. 
Freeport  &  Mexican  Fuel  Oil  Corpn  

3,626,917 

3,939,756 

4,753,862 

8,300,045 

Gulf  Oil  Corpn. 
Mexican  Gulf  Oil  Co  .    . 

1  121  236 

1  734  191 

4  574  520 

10  573,622 

East  Coast  Oil  Co 

3  390  939 

3  398  459 

4  639  513 

5  542,820 

Island  Oil  and  Transport  Corpn  

6,212,915 

12,410,323 

Pierce  Oil  Corpn  

636,469 

1,253,133 

977,730 

2,312,039 

Union  Oil  Company  of  California  

1,622,131 

2,002,453 

68,811 

Cities  Service  Co. 
National  Petroleum  Corpn  

258,894 

543,791 

489,159 

792,050 

New  England  Fuel  Co      .    . 

166  567 

218  244 

1,126,967 

Cochrane  and  Harper 

•  335  571 

1,187,915 

Inter-ocean  Oil  Co  

619  056 

492  511 

635  296 

438,754 

293,719 

400,094 

National  Oil  Co          

1,602,134 

Atlantic  Gulf  Oil  Co. 
Compania  Refinadora  del  Agwi 

6,403,967 

Total      

42  545  843 

51  766  116 

80  701  780  * 

146,489,120 

*  Includes  2,998,491  bbl.  Mexican  coastwise  shipments  that  were  consumed  domestically,  making 
net  exports  77,703,289  bbl. 


VALENTIN   R.    GARFIAS 


535 


TABLE    9. — Tank   Steamers   in   Operation  and   Under  Construction 
Companies  Exporting  Mexican  Oils 


Company 

In  Operation 

Under  Construction 

Number 
of 
Tankers 

Total 
Dead- 
weight 
Tons 

Maximum 
Tonnage 
per 
Tanker 

Number 
of 
Tankers 

Total 
Dead- 
weight 
Tons 

Maximum 
tonnage 
_Pefi 
Tanker 

Atlantic  Gulf  Oil  Co 

16 
4 
15 

1 
18 
2 

11 

19 
45 
15 
12 

221,000 
25,000 
106,777 
5,100 
145,325 
10,000 
263,000 
50,884 

109,039 
449.166 
100,000 
82,875 

18,100 
8,000 
12,777 

12,350 
5,000 

7,500 

12,650 
15,000 
9,500 
11,000 

14 
7 

4 
11 

12 

15 
17 

8 

160,400 
126,000 

30,270 
150,000 

116,600 

159,960 
225,000 
80,000 
89,000 

12,000 
20,000 

10,300 
12,000 

10,500 

12,650 
20,000 
10,000 
12,000 

Eagle  Oil  and  Transport 

East  Coast  Oil  Co 

Gulf  Refining  Co 

National  Petroleum  Corpn 

Pan  American  Petroleum  &  Transp.  .  . 
Pierce  Oil  Corpn*.             .    . 

Shell  Transport  Co  t 

Sinclair  Consolidated  Oil  Corpn 

Standard  Oil  Group 
Standard  Oil  Co.  of  N.  Y.f        

Standard  Oil  Co.  of  N.  J.f  
The  Texas  Co  

Union  Oil  Company  of  California!.  .  •  • 

*  It  is  acknowledged  that  the  information  on  this  table  is  incomplete. 
t  Only  a  small  number  of  these  tankers  are  in  the  Mexican  trade. 

PRODUCTION  AND  EXPORTS 
Mexican  and  American  Oil-measuring  Standards 

The  standards  for  measuring  oil  in  Mexico  are  based  on  the  metric 
system  and  so  the  weight  of  water,  which  is  the  basis  for  comparison  with 
oil,  is  taken  with  water  at  a  temperature  of  4°  C.  and  the  specific  gravity 
of  oil  is  based  on  oil  at  20°  C.;  the  American  standards  are  taken  on  the 
basis  of  the  relative  densities  of  oil  and  water  at  60°  F.  (17°  C.).  It  is 
therefore  evident  that  oil  having  a  specific  gravity  of,  say,  0.982  under 
the  Mexican  standards  is  not  an  oil  of  0.982  specific  gravity  under  the 
American  standards.  In  order  to  establish  the  relation  between  both 
systems,  Table  3  has  been  compiled;  this  gives  the  specific  gravities  and 
Baume"  degrees  in  the  American  standard  and  the  corresponding  specific 
gravities  in  the  Mexican  standard,  and  also  the  volume-weight  relation 
showing  the  number  of  barrels  per  metric  ton. 

The  Mexican  Government  levies  the  tax  on  the  weight  of  the  oil, 
pesos-per-metric-ton  basis,  while  the  American  operator  sells  the  product 
by  volume  on  the  dollars-per-barrel  basis. 

Relation  between  World}  United  States,  and  Mexican  Production 

A  clear  idea  of  the  Mexican  oil  production  and  exports  may  be 
obtained  from  Table  4  and  Fig.  1,  which  show  that  for  the  first  seven 
years,  Mexico's  yearly  production  did  not  reach  1  per  cent,  of  the  world's 
total;  that  the  increase  in  production  was  gradual  until  the  light-oil  fields 
were  discovered,  in  1910,  from  which  date  there  has  been  a  rapid  increase, 


536  PRODUCTION,  TRANSPORTATION  &  TAXATION  OP  MEXICAN  PETROLEUMS 

until  the  Mexican  production  aggregates  about  28  per  cent,  of  the  world's 
total.  The  greatest  portion  of  the  Mexican  production  is  exported,  the 
exports  began  in  1911  and  reached  an  important  amount  in  1913.  About 
three-fourths  of  the  exports  go  to  the  United  States,  in  1920  this  amounted 
to  over  112,000,000  bbl.  During  1920,  the  United  States  and  Mexico 
produced  on  an  aggregate  close  to  95  per  cent,  of  the  total  world's  output. 


1917 

FIG.  1.— MEXICAN  OIL 


1918 


1919 


EXPORTS,  BY  PORTS  FROM  WHICH  EXPORTED,  AND  TOTAL  TO 
THE  UNITED  STATES. 


Summary  of  Mexican  Production 

Table  5  gives  an  analysis  of  Mexican  production,  exports,  bunker  fuel, 
stocks,  and  domestic  and  field  consumption  during  the  last  four  years. 
It  shows  that  production  has  increased  three  and  one-half  times  during 
this  period,  domestic  consumption  has  likewise  increased,  while  the 
volume  of  oil  stocks  or  in  storage  has  remained  practically  constant .  The 
figures  relating  to  domestic  consumption,  losses,  and  storage  shown  in 
the  table  are  admittedly  only  approximately  correct. 

The  following  table  gives  the  storage  capacity  in  the  Mexican  fields 
during  1919  and  in  August,  1920: 

STORAGE  CAPACITY,  IN  U.  S.  BARRELS 

1919  AUGUST,  1920 

Steel  tanks 26,355,000  31,455,000 

Concrete  tanks 275,000  275,000 

Earthen  reservoirs 22,005,000  22,060,000 

Concrete  reservoirs 865,000  860,000 


Total 49,500,000    54,650,000 


VALENTIN  R.   GARFIAS 

The  steel  storage  facilities  of  four  of  the  large  companies  is  as  follows: 

BARRELS 

Mexican  Eagle 7,120,000 

Mexican  Petroleum 6,500,000 

La  Corona 2,500,000 

Transcontinental 2,200,000 


537 


Exports  by  Destination 

Table  6  and  Fig.  2  show  that  by  far  the  greatest  bulk  of  the  oil  ex- 
ported from  Mexico  goes  to  the  United  States,  South  American  harbors 


1911  1918  1919 

FIG.  2. — MEXICAN  OIL  EXPORTS  BY  DESTINATIONS. 

coming  next;  the  balance  of  the  exports,  a  comparatively  small  sum,  go 
to  widely  scattered  ports  in  the  West  Indies,  Great  Britain,  the  Mediter- 
ranean, and  elsewhere. 

The  amount  of  oil  used  as  bunker  fuel  is  increasing  at  a  rapid  rate, 


538  PRODUCTION,  TRANSPORTATION  &  TAXATION  OF  MEXICAN  PETROLEUMS 

for  the  first  six  months  of  1920  being  about  equal  to  the  total  for  the 
preceding  year.  The  Mexican  coastwise  movements  include  oil  shipped 
from  Tampico,  Tuxpam,  and  Port  Lobos  to  Mexican  harbors  and  to  the 
Aguila  company's  refinery  at  Minatitlan.  The  harbor  of  Tampico  still 
retains  the  leadership  in  oil  exports  with  59  per  cent.,  Port  Lobos  comes 
second  with  29  per  cent.,  and  Tuxpam  third  with  12  per  cent. 

The  oil  shipped  to  Puerto  Mexico  is  refined  at  Minatitlan  and  thence 
marketed  in  Mexico  or  foreign  countries  by  the  Mexican  Eagle  Oil  Co. 
A  small  amount  of  oil  produced  in  the  Tehuantepec  region  is  likewise 
refined  at  Minatitlan,  it  being  difficult  to  differentiate  between  this  pro- 
duction and  the  crude  from  Tuxpam  or  Tampico,  included  under  "Coast- 
wise shipments. " 

The  yearly  over-all  exports  from  Puerto  Mexico  have  been  approxi- 
mately as  follows : 

BARRELS  BARRELS 

1913 1,003,000  1917 1,401,000 

1914 1,846,000  1918 1,010,000 

1915 1,933,000  1919. 1,882,000 

1916 1,536,000  1920 2,300,000  (estimated) 

Table  7  shows  that  since  January,  1917,  most  of  the  oil  exports  had 
gone  to  New  York,  Baltimore,  Philadelphia,  and  neighboring  ports;  over 
one-half  of  the  Mexican  oil  exported  to  the  United  States  going  to  ports 
on  the  Atlantic  seaboard.  The  exports  to  Texas  ports  have  aggregated 
about  one-fourth  of  the  total  exports  to  the  United  States,  this  figure 
being  kept  more  or  less  constant  since  1917,  while  the  exports  to  New 
Orleans  have  gradually  decreased  from  20  to  about  13  per  cent.  The 
exports  to  Florida  ports  have  likewise  decreased  from  10  to  5  per  cent, 
and  those  to  New  England  ports  have  had  a  correspondingly  gradual 
increase.  The  exports  to  California  harbors  aggregate  a  fractional 
percentage  of  the  total  and  consist  for  the  most  part  of  about  5  to  15 
shiploads  during  1919  and  the  first  half  of  1920. 

Exports  by  Companies 

Table  8  shows  that  the  Standard  Oil  group  easily  lead  at  the  present 
time,  the  Mexican  Petroleum  being  second;  the  exports  by  the  Anglo- 
Dutch  interests  are  third,  but  they  have  approximately  only  one-half 
the  exports  of  the  first  group  of  companies.  A  number  of  independent 
companies  exported  from  8,300,000  to  68,000  bbl.  each  during  the  year 
1920. 

It  is  interesting  to  note  that  only  about  sixteen  companies,  or  rather 
interests,  are  at  present  exporting  Mexican  oil,  the  transporting  and 
marketing  of  Mexican  oil  being  thus  narrowed  down  to  the  well-estab- 
lished oil  interests. 


VALENTIN  R.    GARFIAS 


539 


Exports  by  Grades  of  Oils 

It  is  difficult  to  obtain  figures  of  exports  of  Mexican  oils  by  grades; 
those  on  which  Fig.  3  is  based  are  more  or  less  approximate.  However, 
this  chart  shows  that  the  exports  of  light  crude  have  increased  tremend- 
ously during  the  last  eight  months,  and  that  there  has  been  but  little 
increase  in  the  exports  of  heavy  crude,  crude  gasoline,  and  fuel  oil.  This 
would  seem  to  indicate  that  refinery  facilities  have  not  been  increased 
during  that  time,  the  increase  in  exports  being  primarily  due  to  the  larger 
volume  of  the  light  crude  now  produced  in  the  Chinampa-Naranjos- 
Alazan  pool. 


1919  I9ZO 

FIG.  3. — TOTAL  MEXICAN  EXPORTS  SINCE  NOVEMBER,  1919. 


COST  OF  TRANSPORTING  MEXICAN  OIL  IN  TANK  STEAMERS 

Tables  6  and  7  show  that  since  January,  1917,  from  70  to  76  per 
cent,  of  the  total  Mexican  exports  have  gone  to  the  United  States;  in 
fact,  were  Mexican  coastwise  shipping,  bunker  fuel,  and  local  deliveries 
excluded,  the  net  percentage  shipped  to  the  United  States  harbors 
would  be  well  over  75  per  cent. 

Table  7  shows  that  over  half  of  the  exports  to  the  United  States  go  to 
Atlantic  seaboard  harbors,  New  York  harbor  and  vicinity  leading  with 
43.3  per  cent.  Approximately  one-fourth  goes  to  Texas  ports,  13.1 


540  PRODUCTION,  TRANSPORTATION  &  TAXATION  OP  MEXICAN  PETROLEUMS 

per  cent,  to  New  Orleans,  the  remaining  15  per  cent.,  or  so,  is  distributed 
between  the  Florida  and  New  England  ports;  the  amount  being  shipped 
to  California  is  almost  negligible.  It  is  therefore  evident  that  in  studying 
the  cost  of  transporting  Mexican  oils  in  tank  steamers,  it  is  necessary  to 
analyze  conditions  governing  the  transportation  between  the  Mexican 
harbors  and  Texas  ports,  New  Orleans,  Florida  ports,  New  York  and  New 
England,  and  primarily  between  Mexico  and  these  last  two  mentioned. 

Net  Carrying  Capacity  of  Tank  Steamers 

The  net  carrying  capacity  of  tank  steamers  plying  between  Mexican 
and  American  ports  has  been  compiled  in  Figs.  4  and  5,  which  show  that 
the  larger  tankers  are  being  used  between  Mexico  and  New  York  and 
New  England  harbors,  the  smallest  being  used  for  the  short  runs  to 


48,000 
45,000 

£42,000 

— 


•£30,000 
^  7JOOO 
«  24,000 
j*  ?  1,0  00 
1  18^000 
|  15,000 

7-  12,000; 


V 


ifi 


a/ 


flS 


iglg 


l= 


I 

'1 

'.? 
i 


1917  1918  1919  1920 

FIG.  4. — TRANSPORTATION  OF  MEXICAN  OILS  IN  TANK  STEAMERS;  NUMBER  OP  TANKERS 
PER  MONTH  AND  AVERAGE  NUMBER  OF  BARRELS  PER  TRIP  TO  ALL  PORTS. 

Texas  and  Florida  ports.  Somewhat  larger  tankers  are  used  from  Tam- 
pico  to  New  Orleans. 

In  a  general  way,  it  may  be  stated  that  the  average  tanker  plying 
between  Mexican  harbors  and  New  England  or  New  York  is  a  10,000- 
deadweight-ton  tanker  or  larger,  able  to  carry  60,000  bbl.  and  more  per 
trip;  that  the  average  tank  steamers  plying  to  New  Orleans  have  a  dead- 
weight tonnage  of  about  8000  tons  with  a  carrying  capacity  of  about 
45,000  bbl.;  the  smaller  tankers  of  3000  to  5000  tons  and  oil  barges  make 
the  run  between  Tampico  and  Florida  and  Texas  ports. 

Fig.  4  gives  the  average  number  of  barrels  transported  per  tank- 
steamer-trip  and  indicates  that  this  has  increased  from  about  28,000  in 
January,  1917,  to  49,000  in  October,  1920,  showing  that  larger  units 
are  being  constantly  put  into  service.  This  figure  also  shows  that  the 
carrying  capacity  decreases  during  the  winter  months. 


VALENTIN  R.    GARFIAS 


541 


9QOOO 


1917 


1918- 


1919 


.19EO 


FIG.  5. — AVERAGE  NET  CARRYING  CAPACITY  PER  TANK  STEAMER  TRIP  FROM  MEXICAN 

TO  AMERICAN  PORTS. 


Distance  from  Tampico  to  American  Ports  and  Time  Required  for  Round 

Trip 

The  distance  from  Tampico  to  American  and  other  ports  and  the 
average  number  of  days  required  to  make  a  round  trip  by  a  tanker,  with 
an  average  speed  of  10  mi.  per  hr.,  allowances  being  made  for  days  lost 
in  repairs,  dry-docking,  etc.  are  as  follows: 


Antofagasta,  Chile 3,668 

Baltimore,  Md 1,951 

Bayonne,  N.  J . 2,030 

Beaumont,  Tex 475 

Boston,  Mass 2,276 

Buenos  Aires,  Argentine  .  5,518 


DISTANCE,  TIME, 
MILES       DATS 

38 
24 
25 
12 
27 
54 


Callao,  Peru 2,874 

Canal  Zone 1,485 

Freeport,  Tex 474 

Fall  River,  Mass 2,131 

Galveston,  Tex 473 

Houston,  Tex 473 


DISTANCE,  TIME, 
MILES       DAYS 


32 
20 
12 
26 
12 
12 


542  PRODUCTION,  TRANSPORTATION  &  TAXATION  OF  MEXICAN  PETROLEUMS 

DISTANCE,  TTMB,  DISTANCE,  TIME, 

MILES     DAYS  MILES     DAYS 

Jacksonville,  Fla 1,361  19  Philadelphia,  Pa 2,000  25 

Key  West,  Fla 907  16  Pt.  Arthur,  Tex 473  12 

Kingston,  Jamaica 1,252  19  Portland,  Me 2,275  27 

Liverpool,  England 4,905  49  Providence,  R.  1 2,131  26 

London,  England 5,201  51  Rio  de  Janeiro 5,417  53 

Marcus  Hook,  Pa 2,000  25  St.  Thomas,  W.  1 1,905  23 

Maurer,  N.  J 2,025  25  San  Francisco,  Calif 4,150  42 

Miami,  Fla 1,048  16  Savannah,  Ga 1,439  20 

Mobile,  Ala 721  15  Southampton,  England . .  5,013  50 

Montreal,  Canada 3,301  37  Sparrows'  Point 1,950  24 

New  Orleans,  La 721  15  Tampa,  Fla 921  16 

New  York 2,030  25  Texas  City,  Tex 475  12 

Norfolk,  Va 1,829  23  Valpariso,  Chile 4,144  42 

Pensacola,  Fla 759  15  Warner's,  N.  J 2,025  25 

The  shortest  trip,  to  Texas  ports,  requires  an  average  of  twelve  days, 
while  fifteen  days  are  allowed  tankers  making  the  New  Orleans  route. 
The  round  trip  to  New  York  harbor  and  vicinity  requires  twenty -five 
days;  for  the  New  England  ports  one  or  two  days  more  are  needed. 

Cost  of  Tank  Steamers 

In  pre-war  days,  the  price  of  a  10,000-ton  tanker  averaged  close  to 
$70  per  ton;  some  of  the  larger  oil  companies  purchased  these  steamers 
for  less.  During  the  war,  the  price  reached  $200  per  ton  and  higher;  but 
some  months  ago,  a  downward  tendency  began  and  it  is  possible  to 
contract  for  tankers  of  10,000  tons  and  over  for  between  $140  and  $150 
per  ton. 

Although  the  transportation  costs  are  based,  in  this  report,  on 
steamers  rated  at  10,000  d.w.  tons,  the  tendency  is  to  increase  the  ca- 
pacity of  the  boats  to  15,000  and  20,000  tons,  as  shown  on  Table  9.  The 
Eagle  Oil  and  Transport,  and  the  Standard  Oil  of  New  Jersey  have 
under  construction  several  20,000-ton  boats. 

As  a  general  rule,  a  boat  built  for  a  tanker  should  carry,  in  barrels, 
on  an  average  six  times  its  deadweight  tonnage;  for  example,  a  10,000-ton 
tanker  should  average  at  least  60,000  bbl.  of  oil  per  trip.  Naturally,  the 
exact  figures  depend,  among  other  factors,  on  the  weight  of  the  oil, 
design  of  tanker,  amount  of  space  needed  for  tanker's  fuel  (more  bunker 
space  will  be  needed  on  longer  trips)  season  of  the  year,  draft  of  boat  as 
compared  to  the  depth  of  water  in  the  loading  and  unloading  harbors, 
etc.  Five-thousand-ton  tankers  will  carry  somewhat  over  30,000  bbl.; 
7000-ton  tankers  about  45,000  bbl.;  10,000  d.w.  ton  tankers  from  60,000 
to  65,000  bbl.;  15,000-ton  tankers  about  95,000  bbl.;  and  20,000-ton 
tankers  about  120,000  barrels. 

As  a  general  rule,  it  has  been  found  more  advantageous  to  equip 
tankers  with  steam  engines  using  fuel  oil  for  steam  generation;  boats 


VALENTIN  R.    GABFIAS  543 

equipped  with  Diesel  type  engines  have  not  given  as  reliable  service  as 
the  steamers. 

Cost  of  Transportation 

Taking  as  a  unit  a  10,000  d.w.  ton  tanker,  able  to  carry  60,000  bbl.  of 

011  and  upward  per  trip,  and  costing  $200  per  deadweight  ton,  which  is 
higher  than  the  present  average  cost,  and  assuming  other  equally  con- 
servative figures,  the  cost  of  transporting  oil  for  round  trips  taking  from 

12  to  30  days  is  shown  in  Fig.  6. 

Thus  the  cost  per  barrel  for  transporting  oil  in  a  10,000  d.w.  ton 
tanker,  from  Tampico  to  Texas  ports,  12  days  round  trip  will  be  42.5c.; 
to  New  Orleans,  15  days,  53c.;  to  Florida  ports,  16  days,  57c.;  and  to 
New  York,  25  days,  88  cents. 

If  the  tanker  only  cost  SI 00  per  ton,  the  correction  factors  in  the 
lower  left-hand  corner  of  Fig.  6  should  be  used;  thus,  the  New  Orleans 
trip  will  cost  39.64c.  per  bbl.  and  not  53  cents. 

In  corroboration  of  the  figures  given  by  the  chart  for  the  cost  of 
transporting  oil,  the  following  is  quoted  from  the  Journal  of  Commerce  of 
July  29,  1920:  "In  closing  the  contracts,  the  United  States  Shipping 
Board  has  agreed  to  charter  sufficient  tank  ships  for  its  transportation 
at  the  Government  rate  of  $6.50  per  deadweight  ton  per  month." 

Allowing  an  average  of  6  bbl.  per  deadweight  and  assuming  that  the 
oil  is  to  be  transported  from  Tampico  to  New  Orleans  in  a  10,000-ton 
tanker  costing  $200  per  deadweight,  making  two  round  trips  per  month, 
the  Shipping  Board  charter  rate  would  give  a  transportation  cost  of 
54.2c.  per  bbl.  against  the  53c.  per  bbl.  obtained  from  Fig.  6. 

It  is  the  opinion  of  competent  authorities  that  for  round  trips  taking 
from  12  to  30  days,  the  various  charges  for  the  shorter  and  longer  trips 
will  about  balance  each  other,  leaving  a  fairly  uniform  ratio  for  cost  of 
transporting  oil  per  barrel  for  the  long  and  short  trip. 

CONCLUSIONS 

1.  The  United  States  and  Mexico  will  produce  on  an  aggregate,  in 
1920,  close  to  90  per  cent,  of  the  total  world's  output  of  petroleum. 

2.  The  Mexican  production,  in  1920,  will  aggregate  over  25  per  cent,  of 
the  world's  total. 

3.  About  75  per  cent,  of  the  Mexican  exports  estimated  at  108,000,- 
000  bbl.  in  1920  go  to  the  United  States,  and  this  represents  about  25 
per  cent,  of  the  United  States  production. 

4.  Of  the  oil  exported  to  the  United  States,  about  52  per  cent,  is 
shipped  to  New  York  and  North  Atlantic  ports;  27.5  per  cent,  to  Texas 
ports;  the  remaining  18.5  per  cent,  to  New  Orleans  and  Florida  ports. 

5.  Although  there  has  been  a  gradual  increase  in  the  exports  of  fuel 


544  PRODUCTION,  TRANSPORTATION  &  TAXATION  OF  MEXICAN  PETROLEUMS 


VALENTIN   R.    GARFIAS  545 

oil,  heavy  crude,  and  crude  gasoline,  the  great  increase  is  due  almost 
entirely  to  the  greater  volumes  of  light  crude  exported. 

6.  The  average  load  per  tank  steamer  trip  from  Mexican  harbors  has 
increased  from  28,000  to  48,000  bbl.  from  January,  1917,  to  August,  1920. 
The  average  load  to  North  Atlantic  and  New  York  harbors  is  close  to 
60,000  bbl.  (10,000-ton  tankers);  about  45,000  bbl.  to  New  Orleans 
(8000-ton  tankers);  30,000  bbl.  to  Texas,  and  Florida  ports  (5000-ton 
tankers).    Tank  steamers  under  construction,  12,000,  15,000,  and  20,000 
tons,  when  placed  in  operation,  should  increase  the  average  net  carrying 
capacity  per  tanker  trip. 

7.  The  transportation  costs  given  in  Fig.  6,  based  on  10,000  d.w. 
ton  tankers,  are  very  conservative;  in  fact,  appreciably  lower  figures 
are  fully  justified  at  present.    The  figures  given  apply  to  boats  owned  by 
the  operating  company,  not  to  chartered  boats. 

8.  No  reliable  figures  of  Mexican  oil  in  storage  are  available. 

MEXICAN  TAXATION  ON  PETROLEUM  AND  ITS  PRODUCTS 

Although  the  following  analysis  of  Mexican  taxation  on  petroleum 
was  made  by  the  writer  when  acting  as  Special  Commissioner  of  the 
Petroleum  Department  of  the  Mexican  Government,  the  conclusions 
drawn  represent  his  own  views,  for  which  the  Mexican  Government  can 
in  no  way  be  held  responsible. 

The  Mexican  Government  at  present  levies  on  petroleum  and  its 
products  not  utilized  in  the  Republic,  the  so-called  Export  Stamp  Tax, 
which  is  based  on  certain  percentages,  varying  with  the  grades  of  oil,  of 
the  prices  of  the  exported  commodity.  These  prices  may  be  determined : 
(1)  as  those  prevailing  within  Mexico;  (2)  prices  in  New  York,  or  other 
American  harbors,  less  marine  transportation  costs;  (3)  the  prices,  any- 
where in  the  United  States,  of  similar  petroleums  as  regards  physical 
properties. 

The  amount  of  the  present  taxes  that  depend  on  oil  prices,  which  in 
turn  can  be  interpreted  in  three  ways,  has  been,  and  is  the  source  of 
misunderstandings  between  some  of  the  operators  and  the  government 
whenever  the  government  and  the  companies'  manner  of  evaluating  the 
oils  disagree.  The  aim  of  the  writer  is  to  pave  the  way  for  the  removal 
of  these  causes  for  controversies  and  to  suggest  changes  that  will  make 
for  a  more  definite  and  clear  basis  for  taxation. 

TAXES  PRIOR  TO  MAY,  1917 

With  the  exception  of  the  usual  stamp  tax  on  documents,  and  such 
other  minor  contributions,  the  oil  companies  operating  in  Mexico  did  not 
pay  taxes  to  the  government  on  about  24,800,000  bbl.  produced  prior  to 

VOL.  LXV. — 35. 


546  PRODUCTION,  TRANSPORTATION  &  TAXATION  OF  MEXICAN  PETROLEUMS 

1912.  In  fact,  companies  like  the  Aguila,  Huasteca,  and  the  Standard 
Oil  of  New  Jersey  were  exempt  from  the  usual  import  taxes  on  machinery, 
etc.  On  July  1,  1912,  during  the  administration  of  President  Madero, 
an  export  tax  of  20  centavos  per  metric  ton,  approximately  1.54  U.  S. 
cents  per  barrel  of  oil  exported,  was  charged :  this  tax,  which  was  applied 
irrespective  of  the  quality  of  the  oil,  was  in  force  until  November,  1913, 
when  it  was  increased  to  75  centavos  per  metric  ton,  about  5.77  U.  S 
cents  per  barrel,  during  the  Huerta  administration.  This  tax,  like  the 
preceding  one,  was  applied  to  oil  exported,  irrespective  of  its  quality, 
and  was  reduced  on  May  1,  1914,  to  60  centavos  per  metric  ton,  approxi- 
mately 4.62  U.  S.  cents  per  barrel,  during  the  Carranza  administration 
and  was  in  force  until  May  1,  1917,  when  the  present  tax,  based  on  a 
certain  per  cent,  of  the  value  of  the  oils  was  established.  The  exports 
from  1912  to  April,  1917,  inclusive,  aggregating  about  111,700,000  bbl., 
were  taxed,  therefore,  approximately  $4,355,000,  or  about  3.9  U.  S.  cents 
per  barrel. 

TAXES  FROM  MAY,  1917  TO  DATE 

It  should  be  understood  that  the  tax,  called  in  this  paper  the  export 
stamp  tax,  applies  exclusively  to  petroleum  and  its  products  and  is  inde- 
pendent of  any  other  former  or  subsequent  tax  that  applies  to  petroleum 
as  well  as  to  other  exports.  Under  this  heading  may  be  included  the 
paper  redemption  tax  (infalsificable),  bar  dues  for  oil  shipped  from  Tampico, 
etc.  It  is  clear,  therefore,  that  when  one  speaks  of  Mexican  taxation  on 
oil,  one  should  differentiate  between  the  export  stamp  tax,  to  which 
the  decree  of  Apr.  13,  1917,  applies  and  which  is  based  on  a  certain 
percentage  of  the  value  of  the  oils,  and  any  other  taxes  not  inherent  to 
the  petroleum  industry.  The  additional  taxes  that  are  not  properly  oil 
taxes  are  small,  compared  with  the  export  stamp  tax. 

THE  EXPORT  STAMP  TAX 

The  decree  of  Apr.  13,  1917,  on  which  this  tax  is  based,  reads  in  part 
as  follows: 

.  .  .  that  it  being  of  very  diversified  quality,  the  petroleum  produced  in  the 
Republic,  and  for  the  same  reason  of  different  commercial  value,  the  tax  should  have 
as  a  basis  the  value  of  each  product,  in  order  that  it  be  reasonable  and  equitable; 
that  a  considerable  quantity  of  this  liquid  is  not  utilized  because  the  necessary  pre- 
cautions are  not  taken  in  the  exploration  work  and  its  daily  handling,  this  circum- 
stance occasioning  frequent  losses,  not  only  to  the  interested  companies,  but  also  to 
the  Government,  on  account  of  the  taxes  that  it  fails  to  collect. 

In  view  of  the  foregoing,  I  (the  President)  have  enacted  the  following  decree: 
Article  1. — All  crude  petroleum  of  national  production,  its  derivatives  and  the 
gas  from  the  wells,  from  the  moment  that  it  flows  from  the  ground  or  leaves  the 
storage  deposits,  are  subject  to  a  special  stamp  tax  under  the  following  terms: 


VALENTIN   R.    GABFIAS  547 

(a)  Crude  and  fuel  oil 10  per  cent,  of  assigned  value. 

Refined  gasoline 3  per  cent,  of  assigned  value. 

Crude  gasoline 6  per  cent,  of  assigned  value. 

Refined  kerosene 3  per  cent,  of  assigned  value. 

Lubricating  oils ^c.  per  liter. 

Asphalt $1 . 50  per  ton. 

Gas 5  per  cent,  ad  valorem. 

(For  up-to-date  rates  and  changes  see  Table  1.) 

(6)  The  crude  petroleum  and  its  derivatives,  when  wasted  in  any  quantity, 
whether  for  lack  of  care  or  not  complying  with  the  legal  regulations,  will  pay  a  tax 
double  the  one  corresponding  to  similar  products. 

The  products  derived  from  the  natural  gas  of  the  wells,  when  it  is  wasted  from  the 
same  reasons,  will  pay  10  per  cent,  of  its  commercial  value. 

Article  2. — (Exempts  from  tax,  oil  consumed  in  Mexico.) 

Article  3.— (Defines  "crude  oil,"  "refined  oils,"  etc.) 

Article  4. — In  order  to  be  able  to  establish  the  tax,  which,  in  accordance  with 
fraction  (a)  of  Article  1,  corresponds  to  each  one  of  the  products  derived  from  petro- 
leum, the  Secretary  of  Hacienda  will  fix  every  two  months  the  prices  of  said  articles 
at  the  shipping  ports,  taking  the  average  of  the  values  reached  in  the  previous  month. 
The  manifestations  or  bills  that  the  companies  present  regarding  sales  of  the  same 
articles,  in  the  interior  in  Mexico,  will  serve  as  a  base  for  making  the  estimate 
referred  to. 

In  case  that  no  operations  of  sales  take  place  in  the  interior,  the  average  value 
which  these  products  had  in  New  York  the  previous  month,  or  in  the  harbors  of  the 
United  States,  will  be  taken,  deducting  the  value  of  transportation  of  said  products, 
from  the  Mexican  to  the  foreign  harbors.  If  there  are  no  available  data  to  make  the 
previous  calculations,  an  equal  price  will  be  assigned  to  that  which  similar  articles 
have,  in  regard  to  physical  properties,  in  the  United  States,  fixing  on  this  price  the 
respective  tax. 

THE  GRADES  OF  MEXICAN  OILS  EXPORTED 

Although  it  is  difficult  to  obtain  accurate  information  regarding  the 
various  grades  of  oils  exported  from  Mexico,  enough  data  has  been  ob- 
tained to  show  that,  at  present  and  for  some  time  past,  the  bulk  of  the 
exports  can  be  divided  into  four  classes: 

Light  or  southern  crude 0 . 9333  sp.  gr.  (20°  Be*.) 

Heavy  or  Panuco  crude 0. 9859  sp.  gr.  (12°  Be".) 

Fuel  oil 0.9589  sp.  gr.  (16°  B<§.) 

Crude  kerosene  or  tops 0 . 7527  sp.  gr.  (56°  Be".) 

The  light  crude  is  exported  in  large  quantities  and  is  also  partly 
refined  in  topping  plants,  which  produce  a  low-flash  fuel  oil  and  light  tops, 
or  crude  gasoline.  The  heavy  crude  is  not  refined,  being  used  exclusively 
for  fuel  purposes  in  power  plants;  its  low  flash  point  and  high  viscosity 
prevent  its  extensive  use  for  marine  purposes. 

MEXICAN  TAXES  ON  VARIOUS  GRADES  OF  OILS 

The  export  stamp  taxes  from  May,  1917,  to  January,  1921,  for  the 
four  main  grades  of  oils,  have  been  computed  and  listed  in  Tables  10  and 


548  PRODUCTION,  TRANSPORTATION  &  TAXATION  OF  MEXICAN  PETROLEUMS 


VALENTIN  R.   QABFIAS 


549 


550  PRODUCTION.  TRANSPORTATION  &  TAXATION  OP  MEXICAN  PETROLEUMS 

13,  on  the  basis  of  U.  S.  cents  per  barrel.  These  tables  show  that  the 
lowest  tax,  3.90c.  per  bbl.,  was  levied  on  heavy  crude  in  1917,  the  highest, 
72.7 rc.  per  bbl.,  or  about  1.73c.  per  gal.,  being  levied  on  crude  gasoline  for 
several  months  in  1920. 

In  a  general  way  the  taxes  on  light  crude  have  gradually  increased 
from  7.8c.,  in  1917,  to  18.2c.,  in  September,  1920;  fuel  oil  tax  has  increased 
from  5.7  to  13c.;  heavy  crude  from  about  4  to  lOc.  and  back  to  8.6c.; 
and  crude  gasoline,  from  1.2  to  1.7c.  a  gallon. 

The  monthly  fluctuation  in  taxes  for  the  four  grades  of  oils  are  graph- 
ically shown  in  Fig.  7,  which  illustrates  the  comparatively  few  changes 
that  have  occurred  from  May,  1917,  to  March,  1920.  The  percentage 
of  increase  in  the  taxes  on  the  various  grades  is  shown  in  Fig.  8,  which 
illustrates  the  abnormal  increase  of  the  tax  on  heavy  crude,  on  March, 
1920,  as  well  as  the  lack  of  uniformity  in  the  fluctuations  of  all  taxes  from 
March,  1920,  to  date. 

The  average  export  stamp  taxes,  in  U.  S.  cents  per  barrel,  paid  from 
1912  to  1917  were:  July,  1912,  to  November,  1913,  1J£;  November,  1913, 
to  May,  1914,  5>^;  May,  1914,  to  May,  1917,  4>^;  irrespective  of  the 
quality  of  the  oils,  while  the  average  from  May,  1917,  to  December, 
1920,  for  the  four  main  grades  of  products  has  been:  Heavy  crude, 
5;  light  crude,  11;  fuel  oil,  9;  crude  gasoline,  56c.  per  bbl.,  or  IJ^c.  per 
gallon. 

Table  11  shows  the  total  taxes  on  petroleum  and  its  products,  which 
include,  besides  the  export  stamp  tax,  others  not  exclusively  applicable 
to  the  oil  industry.  This  table  shows  the  infalsificable,  or  paper  re- 
demption tax  (one  paper  peso  be  paid  for  each  metal  peso  paid  in  taxes) 
figured  on  the  uniform  ratio  of  10  to  1  for  the  relative  values  of  the 
paper  and  metal  peso,  which  ratio  undoubtedly  gives  larger  figures  than 
have  been  actually  paid.  Bar  dues  have  been  calculated  on  the  assump- 
tion that  all  the  oil  exported  paid  these  bar  dues,  while,  as  a  matter  of  fact, 
these  dues  are  applicable  only  to  the  oil  shipped  from  the  harbor  of 
Tampico. 

The  total  taxes  herein  listed  represent  practically  all  the  returns  the 
Mexican  Government  obtains  from  the  oil  industry,  inasmuch  as  no 
income  nor  excess  profit  or  similar  taxes  are  in  operation  in  Mexico. 

THE  VALUE  OF  MEXICAN  OIL 

The  statement  has  been  often  made  that  the  export  stamp  tax,  which 
by  law  should  represent  10  per  cent,  of  the  price  of  the  oil,  actually 
amounts  to  40  per  cent.,  but  the  absurdity  of  such  statements  can  be 
realized  by  analyzing  the  average  taxes  from  1917  to  date.  On  the 
assumption  that  these  taxes  represented  40  per  cent,  of  the  prices  of  the 
oils,  we  would  have: 


VALENTIN   R.    GABFIAS  551 

PBICE  IN  MEXICO 


Heavy  crude 

40  PEE  CENT.  TAX 
5c 

U.  S.  CENTS 
12^  per  bbl 

Light  crude  

He. 

27K  per  bbl. 

Fuel  oil 

9c. 

22)^  per  bbl. 

Crude  easoline  .  . 

l^c.  oer  eal. 

3K  t>er  eal. 

The  computed  prices  in  this  case  fall  far  below  the  market  price,  as 
any  one  familiar  with  conditions  can  certify.  This  comparison  illus- 
trates, further,  the  difficulties  encountered  in  ascertaining  whether  the  tax 
in  question  is,  or  is  not,  the  exact  percentage  marked  by  law  of  a  price 
that,  according  to  the  law,  can  be  computed  in  three  ways,  none  of  which 
is  clearly  enough  defined  to  eliminate  possibilities  of  misunderstandings. 

It  has  been  advanced  by  representatives  of  some  companies  that  the 
only  proper  basis  for  arriving  at  the  true  value  of  Mexican  oils,  say  at 
Tampico,  will  be  found  in  the  selling  contracts  made  between  companies, 
or  between  an  oil  company  and  the  U.  S.  Shipping  Board,  which  stipulate 
the  price  at  the  Mexican  harbor.  In  support  of  this  contention,  con- 
tracts are  exhibited  showing  the  prices  of  Mexican  oils  varying  within 
wide  limits,  but  as  a  rule  well  below  what  might  be  considered  a  fair 
market  value.  It  is  further  stated,  by  the  supporters  of  this  method  of 
appraising  Mexican  oils,  that  account  should  be  taken  of  long  term  con- 
tracts which  net  the  companies  relatively  low  figures  at  the  present 
time. 

On  the  other  hand,  it  should  be  evident  to  any  one  familiar  with  inter- 
companies'  oil  contracts,  that  they  do  not  offer  the  best  means  of  ascertain- 
ing  the  fair  market  price,  as  shown  by  the  following  examples:  Producing 
company  A  sells  its  oil  at  Tampico  to  transportation  company  B  at  a 
price  that  will  net  little  or  no  profit  to  the  producing  company.  Com- 
pany B,in  turn,  sells  the  oil  in  the  United  States  to  marketing  company  C 
for  a  price  that  will  allow  the  transportation  company  to  operatejts 
boats  at  a  fair  profit,  leaving  to  the  marketing  company  the  big  margin  of 
profits  in  disposing  of  the  products  to  consumers  in  the  United  States. 
It  certainly  would  be  unfair  to  claim,  in  this  case,  that  the  inter-company 
contract  price  between  A  and  B  should  be  taken  as  the  fair  price  of  the 
oil  at  Tampico. 

A  second  case  will  give  another  view  of  this  same  question.  Produc- 
ing company  A,  when  in  great  need  of  financial  assistance,  was  forced  to 
sell  its  production  to  outside  company  B  on  a  long-term  contract  at  a 
price  that  is  now  considerably  lower  than  the  market  price;  it  is  decidedly 
unfair  to  claim  that  the  contract  price  in  question  represents  the  actual 
market  conditions  for  the  duration  of  the  contract. 

There  is  also  the  case  of  a  long-term  contract  made  under  profitable 
terms  in  years  past,  but  with  poor  judgment  as  to  future  prices  of  Mexi- 
can oils.  It  would  be  unfair  to  claim  that  the  prices  stipulated  in  these 


552  PRODUCTION,  TRANSPORTATION  <fc  TAXATION  OP  MEXICAN  PETROLEUMS 

contracts  always  represent  actual  market  conditions  when  the  net  result 
is  only  to  shift  profits  from  one  company  to  another. 

The  U.  S.  Shipping  Board  has  made  contracts,  principally  for  oils 
that  the  Shipping  Board  could  not  use  without  refining,  and  the  price  of 
the  oil  transported  was  one  of  the  many  clauses  in  the  contracts.  These 
contracts  often  included  certain  trading  agreements  for  fuel  oils  that  could 
be  utilized  as  bunker  fuel,  the  price  of,  say,  the  light  crude  contracted, 
refining  of  the  crude,  preferential  rights  for  additional  transportation 
facilities,  etc.  Here  again,  the  contract  price  might  well  not  reveal  the 
actual  market  price  of  the  crude. 

Were  the  letter  and  not  the  spirit  of  the  1917  law  followed  a  tax  on 
gasoline  of  about  2%  U.  S.  cents  per  gallon  would  be  justified,  in  place 
of  the  present  tax  of  1.7  U.  S.  cents  per  gallon,  if  the  current  Tampico 
price  of  gasoline  were  taken  into  account. 

Summarizing  the  foregoing,  it  may  be  safely  concluded  that  as  long 
as  the  export  stamp  tax  is  based  on  the  prices  of  oils  in  Mexico,  as  defined 
in  the  decree  of  April,  1917,  the  result  will  be  endless  controversies 
between  the  Mexican  Government  and  the  operating  companies. 

RELATION  BETWEEN  PRICES  OF  AMERICAN  AND  MEXICAN  OILS 

It  should  be  clearly  understood  that  by  the  following  analysis  the 
writer  does  not  intend  to  establish,  for  instance,  a  direct  ratio  between 
the  prices  or  values  of  Mid-Continent  crude  at  the  well  and  those  of 
Mexican  petroleum,  nor  that  the  composition  of  Mexican  light  crude 
corresponds  to  that  of  Gulf  Coast,  Mid-Continent,  or  Californian  crudes, 
nor  that  the  price  of  Mexican  oil  be  established  by  comparison  with  the 
fluctuations  in  prices  of  one  or  all  of  the  American  oils  mentioned.  The 
endeavor  is:  (1)  To  analyze  the  fluctuations  in  price  of  the  bulk  of  Ameri- 
can oils,  viz:  Mid-Continent,  Californian  and  Gulf  Coast,  which  aggre- 
gate about  85  per  cent,  of  the  total  production  of  the  United  States ;  (2) 
to  establish  the  history  of  market  fluctuations  of  these  oils  and  such  other 
closely  related  products  as  bituminous  coal  so  that  the  average  would 
represent  a  fairly  stable  picture  of  over-all  market  fluctuations,  independ- 
ent of  the  control  of  any  one  interest  (official  or  otherwise)  and  solely 
related  to  the  laws  of  supply  and  demand;  (3),  once  this  bench  mark  is 
established,  to  ascertain  the  relation  between  the  Mexican  ad  valorem 
taxes  levied  from  beginning  to  date  and  these  average  prices,  not  with 
the  view  of  deciding  what  the  price  of  Mexican  oils  has  been,  but  in  an 
effort  to  ascertain  what  relation  has  existed  between  Mexican  taxes  and 
such  independent  standard  on  which  future  taxation  could  be  based  thus 
eliminating  past  controversies  between  the  Mexican  Government  and  the 
operating  companies.  The  writer  wishes,  therefore,  to  emphasize  at 
this  time  that  what  results  are  given  are  not  offered  as  the  solution  of  the 


VALENTIN  R.    GARFIAS 


553 


554  PRODUCTION,  TRANSPORTATION  &  TAXATION  OF  MEXICAN  PETROLEUMS 

question  as  to  what  really  has  been  or  is  the  value  of  Mexican  oils  in 
American  harbors,  but  are  only  presented  as  offering  a  new  and  impartial 
basis  for  taxing  the  Mexican  oils  exported. 

As  the  law  of  April,  1917,  provided  that  the  value  of  oils  in  the  United 
States  may  be  taken  into  account  after  proper  allowances  are  made  for 
the  cost  of  transporting  the  oil  from  the  Mexican  to  the  American  harbors, 
realizing  the  many  difficulties  encountered  in  reaching  satisfactory  results 
by  using  the  prices  in  Mexico  as  per  companies7  contracts,  etc.,  the 
writer  compiled  detailed  information  on  the  fluctuation  of  oil  values  in 
the  United  States  from  1917  to  date;  first,  to  ascertain  whether  there  has 
been  over-all  market  conditions  uniformly  affecting  the  value  of  American 
oils  in  the  western,  southern  and  central  fields,  and,  second,  to  ascertain 
what  relation,  if  any,  exists  between  the  values  of  the  American  and 
Mexican  products. 

The  average  oil  prices  listed  related  to  the  production  of  the  Mid- 
Continent,  California  and  Gulf  Coast  fields  and  therefore  represent  over- 
all market  conditions.  Fig.  9  and  Table  12  show  that  there  exists  an  over- 
all market  condition  uniformly  regulating  fluctuations  in  prices  of  fuels. 
As  about  50  per  cent,  of  the  Mexican  exports  are  delivered  to  the  Atlantic 
seaboard,  it  was  thought  advisable  to  include  in  the  analysis  the  export 
price  of  bituminous  coal,  with  which  Mexican  oil  comes  directly,  or 
indirectly,  in  competition,  the  ratio  of  1  ton  of  coal  to  3J^  bbl.  of  oil, 
which  is  the  generally  accepted  equivalent,  being  decided  upon,  and  the 
export  price  of  coal  being  converted  to  the  barrel-of-oil  basis.  The 
fluctuations  of  prices  of  bituminous  coal,  as  shown  in  Fig.  9,  are  more 
uniform  than  the  oil  prices,  and  more  closely  follow  the  average  market 
conditions. 

The  Mexican  exports  to  the  United  States,  which  are  75  per  cent,  of 
the  total  exports,  equal  about  25  per  cent,  of  the  American  oil  production, 
so  when  it  is  sold  on  the  Atlantic  or  Gulf  Coast  seaboards,  it  has  to  compete 
with  the  United  States  petroleums;  therefore,  the  price  of  the  Mexican 
oil  is  controlled  by  that  of  the  home  product.  Fig.  9  shows  that  from 
the  end  of  1919  to  date,  there  has  been  a  sharp  increase  in  the  prices  of 
fuels,  both  liquid  and  solid,  throughout  the  United  States,  and  it  is  in- 
conceivable that  the  prices  of  Mexican  oils,  the  bulk  of  which  is  marketed 
in  the  United  States,  did  not  follow  these  over-all  market  fluctuations  of 
values. 

RELATIVE  COST  OF  OPERATING  IN  MEXICAN  AND  AMERICAN 

OIL  FIELDS 

The  claim  is  often  made  by  some  operators  that  the  Mexican  oil 
taxes  should  be  reduced  because  of  the  high  cost  of  development  com- 
pared with  this  cost  in  the  United  States.  But  it  has  been  proved  that 


VALENTIN   B.    GABFIAS  555 

the  aver-all  costs  are  lower  in  the  Mexican  than  in  the  American  fields, 
for  the  average  depth  of  wells  in  the  Mexican  fields  is  less  than  2500  ft., 
which  is  no  greater  than  that  in  most  American  fields,  and  while  the  cost 
of  drilling  is  somewhat  greater,  it  is  certainly  not  much  in  excess  of 
drilling  wells  of  the  same  depth  in  American  fields  where  conditions  are 
similar. 

In  some  American  fields,  the  production  cost,  made  up  mostly  of  the 
cost  of  bringing  the  oil  from  the  underground  reservoirs  to  the  surface, 
is  about  40c.  per  bbl.,  and  as  the  life  of  the  well  decreases,  the  production 
cost  materially  increases.  On  the  other  hand,  the  production  cost  in 
Mexican  fields  is  exceedingly  low,  because  practically  all  the  wells  are 
gushers  that  flow  marketable  oil,  necessitating  no  dehydration.  The 
cost  of  pipe  lines  in  the  Mexican  fields  is  not  materially  greater  than  in 
some  United  States  fields;  the  Mexican  pipe  lines,  as  a  rule,  are  a  good 
deal  shorter  than  the  average  lines  from  the  American  oil  fields  to 
sea-board. 

But  the  main  reason  for  the  lower  operating  cost  in  the  Mexican  fields 
can  be  found  in  Table  1.  In  order  to  produce,  in  round  figures,  100,000,000 
bbl.  per  year,  it  is  necessary  in  California  to  pump  about  9400  wells,  while 
in  Mexico  250  wells  produce  a  greater  amount  by  natural  flow.  In 
fact,  the  number  of  wells  actually  producing  in  Mexico  is  much  nearer 
100  than  250.  The  California  well  averages  about  29 J^  bbl.  per  day, 
while  the  productivity  of  the  Mexican  wells  ranges  (according  to  whether 
we  class  as  producers  every  well  capable  of  producing  or  only  those 
actually  producing)  between  1190  bbl.  and  3000  bbl.  per  day.  Cali- 
fornia conditions  are  well  above  the  average  in  the  United  States,  as  the 
228,000  wells  producing  in  the  country  only  average  about  5J^  bbl.  per 
well  per  day,  as  compared  with  29^  bbl.  for  the  California  wells.  Besides 
these  producing  wells,  in  the  United  States  and  Mexico,  many  dry  holes 
have  been  drilled;  about  6000  wells  have  been  abandoned  each  year  from 
1913  to  1917  inclusive  in  the  United  States  while  the  total  number  of 
wells  abandoned  in  Mexico  to  date  is  less  than  600. 

These  statistics  prove  the  low  cost,  everything  considered,  of  operat- 
ing in  the  Mexican  oil  fields;  a  closer  analysis  discloses  the  fact  that  in  no 
other  oil  field  have  such  economical  conditions  for  operations  prevailed 
as  in  the  Mexican  fields  to  date. 

RELATION  BETWEEN  AVERAGE  OIL-COAL  PRICE  AND  MEXICAN 

TAXES 

The  average  prices  of  American  petroleums  and  bituminous  coal, 
which  represents  market  conditions  of  these  commodities  in  the  United 
States,  are  given  in  Tables  12  and  13  and  are  graphically  shown  in  Figs. 
7  and  10.  These  records  show  a  gradual  increase  in  the  average  price, 


556   PRODUCTION,  TRANSPORTATION  &  TAXATION  OF  MEXICAN  PETROLEUMS 


VALENTIN   R.    GARFIAS  557 

from  $1.10  per  bbl.  in  January,  1917,  to  $1.60  per  bbl.  in  Decem- 
ber, 1919,  followed  by  an  increase  during  1920,  from  $1.60  to  $2.77. 
The  average  price  increased,  therefore,  45.5  per  cent,  during  the  years  of 
1917  to  1919  inclusive,  and  73  per  cent,  in  the  first  eleven  months  of  1920; 
the  over-all  fluctuations  from  January,  1917,  to  November,  1920,  repre- 
sent close  to  15.2  per  cent. 

Table  13  shows  the  per  cent,  relations,  by  months,  between  the  average 
oil-coal  price  and  the  export  stamp  tax  on  the  four  grades  of  oils  exported; 
the  figures  indicating  that  the  average  tax  on  light  crude  corresponds 
approximately  to  7  per  cent,  of  the  type  price  (see  Fig.  10),  the  percentage 
during  August,  1920,  of  5.98  being  about  the  lowest  recorded;  the  tax  on 
fuel  oil  represents  on  an  average,  5.4  per  cent,  of  the  oil-coal  price,  the 
tax  for  August,  1920  being  in  proportion  the  lowest  so  far  levied. 

This  analysis,  based  on  facts,  clearly  shows  that  the  Mexican  export 
stamp  taxes,  with  the  possible  exception  of  that  on  heavy  crude,  are 
lower  in  relation  to  the  average  market  conditions,  at  the  present  time, 
than  when  initiated  in  May,  1917. 

TAX  CONTROVERSIES  BETWEEN  MEXICAN  GOVERNMENT  AND  OIL 

COMPANIES 

Although  a  number  of  important  foreign  companies  have  always  worke^ 
in  harmony  with  the  Mexican  Government,  as  was  stated  to  the  writer  by 
their  representatives  in  the  course  of  this  investigation,  other  companies 
have  questioned  any  increase  in  taxation  with  the  resulting  controversies 
between  these  companies  and  the  government  whenever  such  changes 
occurred. 

It  is  undoubtedly  true  that  the  principle  on  which  the  present  Mexi- 
can tax  operates  has  not  been  successful,  nor  has  it  met  in  its  application 
with  the  full  approval  of  most  of  the  operating  companies.  This  is  due 
not  so  much  to  the  amount  of  taxes  actually  paid  as  to  the  inability  of 
the  operators  to  foretell  when  or  what  increases  will  take  place,  thus 
preventing  sellers  and  purchasers  from  taking  proper  care  of  these  changes 
at  the  time  of  fixing  contract  prices  that  extend  for  considerable  time. 
This  has  raised  difficulties  between  buyer  and  seller,  the  former  in  some 
cases  being  willing  only  to  agree  to  pay  the  prevailing  tax  when  the  con- 
tract is  made,  thus  leaving  the  seller  unable  to  collect  any  additional 
amount  in  case  the  tax  is  increased  before  the  expiration  of  the  contract. 

It  appears,  therefore,  that  although  the  operators  are  not  justified  in 
asking  for  a  reduction  of  the  present  tax,  in  order  to  safeguard  the  inter- 
ests of  bona  fide  marketers  the  Mexican  tax  should  be  revamped  to 
conform  with  the  usual  business  transactions  between  buyer  and 
seller. 


558  PRODUCTION,  TRANSPORTATION  &  TAXATION  OF  MEXICAN  PETROLEUMS 


I 

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oo'o'd 


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o'  o  o  o' 


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05  0500 


COOJOSt- 


VALENTIN   R.   GARFIAS 


559 


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coo>ooo 

CO  CO  N  <3> 

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ooo 

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OO«OO--i'-"O 

SoSS 

oooocsSco 

So^S 

88Sg«5S 

Is§5 

oooolSco 

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CNU5CSO 

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fH 

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1-HiH         l-H 

CO>OO>O 

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S2S§ 

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<N>H^HIO 

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laws! 

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cooo»o»o 
dodo 

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o'do'd 

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0505O5t- 

0000 

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560  PRODUCTION,  TRANSPORTATION  A  TAXATION  OP  MEXICAN  PETROLEUMS 


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VALENTIN   R.    GARFIAS 


561 


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... 
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'  '  <i'lo  gsHolinn 
Keroiene,  orude  or  refined 


Crude. 
Fuel  oil..., 


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Crude 
Crude. 
Gft»oll 
Unfilled  KiiM 
Crude  «a»iol 
Keroiene,  o 


<!rude 
Fuel  oil 


562  PRODUCTION,  TRANSPORTATION  A  TAXATION  OF  MEXICAN  PETROLEUMS 


.2*  * 


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Crude  

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Gas  oil  
Refined  gasoline  

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Crude  
Fuel  oil  

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VALENTIN   R.    GARFIAS 


563 


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§§§§§§§ 


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oooo 


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oooo 


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COOO»O»O 
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oooo 


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CO  OS  OS  OS 

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CO  00  10  10 
OS  OS  OS  N- 


e 
l  oil 
de  gas 


I 
ii 

•3-3" 

£& 


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Fuel  o 


564  PRODUCTION,  TRANSPORTATION  &  TAXATION  OF  MEXICAN  PETROLEUMS 

CONCLUSIONS  AND  RECOMMENDATIONS 

The  foregoing  discussion  clearly  indicates:  (1)  That  the  rate  of 
Mexican  taxation  on  oil  exported  and,  in  fact,  the  aggregate  of  all 
Mexican  taxes  affecting  the  oil  industry,  far  from  being  burdensome  in 
nature  as  some  operators  contend,  have  been  and  are,  if  anything, 
reasonably  low.  (2)  Mexican  oils  exported  prior  to  May,  1917,  were 
taxed  only  about  4  U.  S.  cents  per  barrel,  and  in  several  cases  the  ex- 
porting companies  were  and  are  exempt  from  paying  the  customary 
import  duties  on  machinery  and  other  supplies  thus  further  benefiting 
from  their  Mexican  operations.  (3)  That  the  export  stamp  taxes  levied 
under  the  decree  of  April,  1917,  are  in  proportion,  lower  in  August,  1920, 
than  in  April,  1917,  when  the  law  was  put  into  effect.  (4)  That  the 
basing  of  the  tax  on  the  price  of  Mexican  oils  in  Mexico,  as  the  decree 
provides,  has  given  rise  to  endless  arguments  and  dissensions.  (5)  That 
the  tax  as  applied  creates  difficulties  between  the  seller  and  purchaser  of 
Mexican  oils,  which  can  and  should  be  eliminated.  (6)  That  it  would  be 
advantageous  to  apply  Mexican  standards  for  measuring  oils,  within 
the  metric  system,  on  the  volume  basis,  rather  than  on  the  weight  basis, 
inasmuch  as  all  Mexican  oil  is  sold  by  volume. 

Keeping  clearly  in  mind  the  rights  of  the  Mexican  Government  as 
well  as  the  just  claims  of  the  operators,  and  realizing  that  many  of  the 
difficulties  can  be  overcome  by  the  establishment  of  some  stable  "bench- 
mark" directly  related  to  market  conditions,  on  which  to  base  the  value  of 
Mexican  oils  and  therefore  the  taxes  on  their  products,  the  writer  offers 
the  following  recommendations: 

1.  That  the  Mexican  tax  on  each  grade  of  exported  oils  be  based  on 
percentages  of  the  average  American  oil-coal  price,  as  defined  in  this 
report.  ' .;.; 

2.  That  these  percentage  relations  between  the  tax  on  any  one  grade 
of  oil  and  the  oil-coal  price  should  remain  practically  constant  unless  new 
conditions  should  develop  to  make  a  change  imperative. 

3.  That,  if  possible,  monthly  variations  of  the  average  oil-coal  price 
be  taken  into  account. 

4.  That  the  tax  be  applied  on  the  volume  (cubic  meter)  rather  than 
on  the  weight  (metric  ton)  of  the  oil  exported  (the  average  oil-coal  price 
in  dollars  per  barrel  converted  to  pesos  per  cubic  meter  is  shown  on 
Table  12). 

5.  That  the  law  of  April,  1917,  be  abrogated  and  a  new  law  enacted 
covering,  in  a  general  way,  the  main  points  herein  advanced. 


VALENTIN  R.    GARFIAS 


565 


TABLE  11. — Total  Mexican  Export  Taxes  in  U.  S.  Cents  Per  Barrel  of 

42  U.  S.  Gal 


and  Month 


Export 

Stamp 

Tax 


Infalsificable  = 

10  Per  Cent,  of 

Export  Stamp  Tax 


Bar  Dues  -  10 

Centavoa  per 

Metric  Ton 


Light  Crude 
20°  Be*. 

May,  1917 7.813  0.781 

September,  1917 9.294  0.929 

November,  1917 j  9.665  0.966 

July,  1918 j  11.145  1.114 

July,  1919 10.775  1.077 

November,  1919 11.145  1.114 

March,  1920 15.713  1.571 

July,  1920 16.698  1.669 

September,  1920 18.179  1.817 

December,  1920 i  18.179  1.817 

Fuel  Oil  ' 
16°  Be*. 

May,  1917 5.737  0.573 

September,  1917 6.878  0.687 

November,  1917 7.258  0.725 

July,  1918 9.160  0.916 

March,  1920 11.913  1.191 

July,  1920 12.201  1.220 

September,  1920 j  12.962  1.296 

December,  1920 1  12.962  1 .296 

Heavy  Crude 
12°  Be*. 

May,  1917 3 . 910  0 . 391 

September,  1917 4.301  0.430 

July,  1918 4.692  0.469 

March,  1920 10. 167  1 .016 

September,  1920 8.603  0.860 

December,  1920 8.603  0.860 

Crude  Gasoline 
56°  Be*. 

May,  1917 52.412  5.241 

September,  1917 53.604  5.360 

January,  1918 55.986  5.598 

March,  1920 67.899  6.789 

May,  1920 72.663  7.266 

September,  1920 67.899  6.789 

December,  1920 67.899  6.789 


0.740 
0.740 
0.740 
0.740 
0.740 
0.740 
0.740 
0.740 
0.740 
0.740 


0.760 
0.760 
0.760 
0.760 
0.760 
0.760 
0.760 
0.760 


0.782 
0.782 
0.782 
0.782 
0.782 
0.782 


0.597 
0.597 
0.597 
0.597 
0.597 
0.597 
0.597 


566  PRODUCTION,  TRANSPORTATION  <fc  TAXATION  OF  MEXICAN   PETROLEUMS 

TABLE  12. — Relation  Between  American  Fuel  Prices  and  Mexican  Export 
Stamp  Taxes  on  Petroleum  and  its  Products 

NOTE.    One  Cubic  Meter  =  6.2899  bbl.    One  U.  S.  dollar  =  Two  Mexican  pesos 


Month  and  Year 

Dollars  per  Barrel 

Pesos  per  Cubic  Meter 

Mid- 
Conti- 
nent 
Crude 

Calif- 
ornia 
Crude 

Bitumin- 
ous Coal 
Export 
Price 
(3.5  bbl. 
per  ton) 

Gulf 
Coast 
Crude 

Average 
Price 

?Se6 

Present  Stamp  Tar 

20° 
Be. 
0.9323 

12° 
Be. 
0.9849 

56° 
Be. 
0.7519 

16° 
Be. 
0.9579 

1917 
May  

1.70 
1.70 
1.70 
1.85 
2.00 
2.00 
2.00 
2.00 

2.00 
2.00 
2.25 
2.25 
2.25 
2.25 
2.25 
2.25 
2.25 
2.25 
2.25 
2.25 

2.25 
2.25 
2.25 
2.25 
2.25 
2.25 
2.25 
2.25 
2.25 
2.25 
2.33 
2.50 

2.97 
3.00 
3.50 
3.50 
3.50 
3.50 
3.50 
3.50 
3.50 
3.50 
3.50 
3.50 

0.82 
0.92 
1.02 
.02 
.02 
.02 
.02 
.02 

.02 
.02 
.02 
.02 
.27 
.27 
.29 
.29 
.29 
.29 
.29 
.29 

.29 
.29 
.29 
.29 
.29 
.29 
.29 
.29 
.29 
.29 
.29 
.29 

.29 
.33 
.33 
.58 
.58 
.58 
.70 
.70 
.70 
.70 
.70 
.70 

0.991 
.011 
.091 
.140 
.100 
.120 
.360 
.017 

.086 
.165 
.147 
.136 
.046 
.105 
.142 
.122 
.148 
.185 
.142 
.194 

.336 
.250 
.428 
.371 
.200 
.250 
.228 
.320 
.400 
.438 
.465 
.380 

.600 
.560 
.615 
.815 
2.028 
2.280 
2.660 
2.957 
2.957 
3.050 
2.870 
2.415 

.00 
.00 
.00 
.00 
.00 
.00 
.00 
.00 

.00 
.00 
.35 
.35 
.35 
.35 
.35 
.35 
.80 
.80 
.80 
.80 

.50 
.25 
.25 
.00 
.00 
.00 
.00 
.00 
.00 
.00 
.00 
.25 

1.75 
2.00 
2.50 
3.00 
3.00 
3.00 
3.00 
3.00 
3.00 
3.00 
3.00 
2.50 

.128 
.158 
.203 
.253 
.280 
.285 
.345 
.259 

.277 
.296 
.442 
.439 
.479 
.494 
.508 
.503 
.622 
.631 
.621 
.634 

1.594 
1.510 
1.555 
.478 
.435 
.448 
.442 
.465 
.485 
.495 
.521 
.605 

1.903 
1.973 
2.236 
2.349 
2.527 
2.590 
2.715 
2.789 
2.789 
2.812 
2.77 
2.529 

14.190 
14.567 
15.133 
15.762 
16.102 
16.165 
16.920 
15.838 

16.064 
16.303 
18.140 
18.102 
18.606 
18.794 
18.970 
18.907 
20.404 
20.518 
20.392 
20.555 

20.052 
18.995 
19.562 
18.593 
18.052 
18.216 
18.140 
i  18.  429 
18.681 
18.807 
19.134 
20.191 

23.939 
24.820 
28.128 
29.550 
31.789 
32.582 
34.154 
35.085 
35.085 
35.375 
34.846 
31.814 

0.983 
0.983 
0.983 
0.983 
.169 
.169 
.216 
.216 

.216 
.216 
.216 
.216 
.216 
.216 
.402 
1.402 
1.402 
1.402 
1.402 
1.402 

.402 
.402 
.402 
.402 
.402 
.402 
.355 
.355 
.355 
.355 
.402 
.402 

.402 
.402 
.977 
.977 
.977 
.977 
2.101 
2.101 
2.287 
2.287 
2.287 
2.287 

0.492 
0.492 
0.492 
0.492 
0.541 
0.541 
0.541 
0.541 

0.541 
0.541 
0.541 
0.541 
0.541 
0.541 
0.590 
0.590 
0.590 
0.590 
0.590 
0.590 

0.590 
0.590 
0.590 
0.590 
0.590 
0.590 
0.590 
0.590 
0.590 
0.590 
0.590 
0.590 

0.590 
0.590 
.279 
.279 
.279 
.279 
.279 
.279 
.082 
.082 
.082 
.082 

6.593 
6.593 
6.593 
6.593 
6.743 
6.743 
6.743 
6.743 

7.043 
7.043 
7.043 
7.043 
7.043 
7.043 
7.043 
7.043 
7.043 
7.043 
7.043 
7.043 

7.043 
7.043 
7.043 
7.043 
7.043 
7.043 
7.043 
7.043 
7.043 
7.043 
7.043 
7.043 

7.043 
7.043 
8.542 
8.542 
9.141 
9.141 
9.141 
9.141 
8.542 
8.542 
8.542 
8.542 

0.722 
0.722 
0.722 
0.722 
0.865 
0.865 
0.913 
0.913 

0.913 
0.913 
0.913 
0.913 
0.913 
0.913 
.152 
.152 
.152 
.152 
.152 
.152 

.152 
.152 
.152 
.152 
.152 
.152 
.152 
.152 
.152 
1.152 
1.152 
1.152 

.152 

.152 
.499 
.499 
.499 
.499 
.535 
.535 
.631 
.631 
.631 
.631 

June  

July             .    . 

August    .... 

September 

October 

November 

December 

1918 
January  .    . 

February  ...          . 

March 

April 

May  

July  

August  

September     

October.  .  .           .... 

November  

December             .    .  . 

1919 
January  

February  

March  

April  

May  

June 

July 

August 

September 

October 

November 

December  
1920 
January  

February  

March  

April  

May  

June 

July 

August    .    . 

September    .    .    . 

October               

December  

VALENTIN   E.    GARFIAS 


567 


TABLE  13. — Mexican  Export  Stamp  Tax  Showing  Percentage  Relation  to 
Average  Oil  and  Coal  Price  from  May,  1917  (in  U.  S.  cents  per  Barrel) 


Year  and  Month 

Average 
Oil  and 
Coal 
Price 

Light  Crude 
20°  Be. 
(0.9323) 

Fuel  Oil 
16°  Be 
(0.9579) 

Heavy  Crude 
12°  B6. 
(0.9849) 

Crude  Gasoline 
56°  Be. 
(0.7519) 

Tax 

Per 

Cent. 

Tax 

Per 

Cent. 

Tax 

Per 

Cent. 

Tax 

Per 
Cent. 

1917 
May 

$1.128 
1.158 
1.203 
.253 
.280 
.285 
.345 
.259 

.277 
.296 
.442 
.439 
.479 
.494 
.508 
.503 
.622 
.631 
1.621 
1.634 

1.594 
1.510 
1.555 
1.478 
.435 
.44S 
.442 
.465 
.485 
.495 
.521 
.605 

.903 
.973 
2.236 
2.349 
2.527 
2.590 
2.715 
2.790 
2.790 
2.812 
2.77 
2.529 

$0.078 
0.078 
0.078 
0.078 
0.093 
0.093 
0.097 
0.097 

0.097 
0.097 
0.097 
0.097 
0.097 
0.097 
0.112 
0.112 
0.112 
0.112 
0.112 
0.112 

0.112 
0.112 
0.112 
0.112 
0.112 
0.112 
0.108 
0.108 
0.108 
0.108 
0.112 
0.112 

0.112 
0.112 
0.157 
0.157 
0.157 
0.157 
0.167 
0.167 
0.182 
0.182 
0.182 
0.182 

6.92 
6.73 
6.50 
6.24 
7.26 
7.23 
7.19 
7.68 

7.56 
7.46 
6.70 
6.72 
6.53 
6.47 
7.39 
7.42 
6.87 
6.83 
6.88 
6.82 

6.99 
7.38 
7.17 
7.54 
7.77 
7.70 
7.47 
7.36 
7.26 
7.21 
6.94 
6.94 

5.86 
5.65 
7.03 
6.69 
6.22 
6.06 
6.15 
5.98 
6.53 
6.47 
6.57 
7.2 

$0.057 
0.057 
0.057 
0.057 
0.069 
0.069 
0.073 
0.073 

0.073 
0.073 
0.073 
0.073 
0.073 
0.073 
0.092 
0.092 
0.092 
0.092 
0.092 
0.092 

0.092 
0.092 
0.092 
0.092 
0.092 
0.092 
0.092 
0.092 
0.092 
0.092 
0.092 
0.092 

0.092 
0.092 
0.119 
0.119 
0.119 
0.119 
0.122 
0.122 
0.130 
0.130 
0.130 
0.130 

5.08 
4.95 
4.77 
4.58 
5.37 
5.35 
5.40 
5.77 

5.68 
5.60 
5.03 
5.04 
6.53 
4.86 
6.07 
6.09 
5.64 
5.62 
5.65 
5.61 

5.75 
6.07 
5.89 
6.20 
6.39 
6.33 
6.35 
6.25 
6.17 
6.13 
6.02 
5.70 

.4.81 
4.64 
5.33 
5.07 
4.72 
4.60 
4.50 
4.38 
4.66 
4.63 
4.70 
5.14 

$0.039 
0.039 
0.039 
0.039 
0.043 
0.043 
0.043 
0.043 

0.043 
0.043 
0.043 
0.043 
0.043 
0.043 
0.047 
0.047 
0.047 
0.047 
0.047 
0.047 

0.047 
0.047 
0.047 
0.047 
0.047 
0.047 
0.047 
0.047 
0.047 
0.047 
0.047 
0.047 

0.047 
0.047 
0.102 
0.102 
0.102 
0.102 
0.102 
0.102 
0.086 
0.086 
0.86 
0.86 

3.46 
3.38 
3.25 
3.12 
3.36 
3.35 
3.20 
3.42 

3.36 
3.32 
2.97 
2.99 
2.91 
2.88 
3.11 
3.12 
2.89 
2.88 
2.88 
2.87 

2.94 
3.11 
3.02 
3.18 
3.27 
3.24 
3.25 
3.20 
3.16 
3.14 
3.09 
2.92 

2.47 
2.38 
4.55 
4.33 
4.02 
3.92 
3.74 
3.64 
3.08 
3.06 
3.10 
3.40 

$0.524 
0.524 
0.524 
0.524 
0.536 
0.536 
0.536 
0.536 

0.560 
0.560 
0.560 
0.560 
0.560 
0.560 
0.550 
0.560 
0.560 
0.560 
0.560 
0.560 

0.560 
0.560 
0.560 
0.560 
0.560 
0.560 
0.560 
0.560 
0.560 
0.560 
0.560 
0.660 

0.560 
0.560 
0.679 
0.679 
0.727 
0.727 
0.727 
0.727 
0.679 
0.679 
0.679 
0.679 

46.45 
45.26 
43.57 
41.82 
41.88 
41.71 
39.85 
42.58 

43.84 
42.53 
38.82 
38.91 
37.85 
37.47 
37.13 
37.25 
34.52 
34.32 
34.54 
34.26 

35.12 
37.08 
36.00 
37.87 
39.01 
38.66 
38.76 
38.22 
37.70 
37.44 
36.80 
34.88 

29.42 
28.36 
30.36 
28.90 
28.74 
28.06 
26.76 
26.04 
24.35 
24.30 
24.50 
26.85 

June        ....        ... 

July  

August  .    .        .... 

September    

October  

November          .  .    . 

December    

1918 
January  

February     

March  

April  

May  

June  

July  

August  

September            .... 

October  

November  

December  

1919 
January  

February  

March 

April  

May 

June 

July.   . 

August 

September 

October 

November 

December 

1920 
January  ,  .  .  . 

February 

March  

April  

May  

June  

July  

August  

September  >. 

October 

November  
December  .... 

568  EFFICIENCY   IN  USE   OF   OIL  AS  FUEL 


Efficiency  in  Use  of  Oil  as  Fuel 

BY  W.  N.  BEST,  D.  So.,  NEW  YORK,  N.  Y. 

(St.  Louis  Meeting,  September,  1920) 

THIS  paper  is  not  intended  as  a  scientific  discussion  of  the  combustion 
of  oil  but  is  written  from  the  standpoint  of  an  operator  who  has  the 
experience  and  qualifications  necessary  to  guide  others  in  producing 
the  most  economical  results  in  the  use  of  liquid  fuels.  Oil,  in  this  paper, 
usually  means  petroleum  or  its  products  but  incidental  reference  is  made 
to  other  liquid  and  gaseous  fuels,  so  that  the  term  may  be  considered 
as  referring  to  all  liquid  and  gaseous  hydrocarbons  in  comparison  with 
solid  fuels,  as  coal  and  wood.  However,  only  a  few  of  the  principal 
factors  in  the  use  of  oil  as  a  fuel  can  be  given. 

The  present,  and  prospective,  high  price  of  coal  is  causing  users  of 
fuel  to  renew  inquiry  as  to  the  merits  of  other  forms  of  fuel  for  industrial 
purposes.  Crude  oil  (petroleum)  is  proving  to  be  one  of  the  world's 
most  valuable  mineral  resources.  The  recent  discovery  that  oil  underlies 
a  considerable  area  of  the  United  States,  Mexico,  and  other  parts  of  the 
world  to  a  greater  extent  than  was  formerly  believed  and  the  large 
production  of  some  of  the  wells  in  these  areas  shows  the  probable  quantity 
of  fuel  oil  that  may  now  be  available.  Through  the  energy  of  Lord 
Cowdrey,  who  was  one  of  the  pioneers  of  the  oil  industry  in  Mexico,  oil 
has  been  discovered  in  England;  some  prominent  geologists  believe  that  it 
may  be  found  in  quantity  in  Great  Britain. 

For  years,  oil  has  been  known  to  be  of  great  value  in  the  manufacture 
of  metals.  It  has  proved  incomparable  in  forge  shops,  steel  foundries, 
heat-treating  furnaces,  and  wherever  accuracy  of  temperatures  is  essen- 
tial, or  where  a  maximum  output  is  desired  as  well  as  quality  of  metal. 
In  some  types  of  equipment,  the  output  produced  with  oil  as  fuel  is 
double  that  obtained  with  coal  and  at  a  reduction  of  50  per  cent,  in  the 
cost  of  the  fuel.  For  example,  in  drop-forging  plants,  the  metal  is  always 
waiting  for  the  man  when  oil  is  used  as  fuel,  whereas  with,  coal,  the  man 
must  wait  for  the  metal  to  become  sufficiently  heated. 

It  has  only  been  since  January,  1919,  that  the  oil  supply  could  be  relied 
on  for  boiler  service,  owing  to  the  war  conditions  and  the  inability  to  get 
oil  tankers  for  the  delivery  of  the  oil  from  Mexico  to  Atlantic  ports; 
but  now  a  constant  supply  is  assured,  and  many  manufacturers  are 
installing  it  in  their  power  plants.  The  cost  varies  with  the  size  of  the 


W.   N.  BEST  569 

plant.  In  New  England  and  along  the  Atlantic  coast,  where  the  boiler 
horsepower  is  large,  this  fuel  is  very  attractive,  for  one  man  can  fire  and 
water-tend  twelve  300-hp.  boilers.  It  raises  the  general  condition  of  the 
man  firing  the  boilers,  because  the  burning  of  oil  is  an  art  and  necessitates 
brain  rather  than  brawn.  This  fuel  responds  immediately  to  the  will  of 
the  operator  in  meeting  peak  or  fluctuating  loads.  The  fire  room  is  clean 
and  sanitary,  dust  from  coal  and  ashes  being  eliminated.  There  is  prac- 
tically no  loss  in  fuel,  as  only  a  small  part  of  the  oil  in  the  storage  tank  is 
heated,  and  that  just  enough  for  it  to  be  pumped  readily  from  the  storage 
tank  to  the  supply  tank.  The  handling  of  the  fuel  is  inexpensive;  and  it  is 
speedily  delivered  from  the  oil  tank  or  tanker.  There  are,  however, 
certain  fundamental  principles  that  must  always  be  observed  in  making 
crude-oil  installations. 

TEMPERATURE  OF  FUEL 

The  temperature  of  the  fuel  and  the  method  of  supply  are  especially 
vital  points.  Oil  below  20°  Be*  should  be  heated  to  just  below  its  vaporiz- 
ing point;  steam  should  always  be  used  for  this  purpose,  as  it  gives  a  very 
accurate  temperature;  the  supply  is  usually  obtained  from  the  exhaust  of 
the  pump.  Numerous  efforts  have  been  made  to  heat  the  oil,  while 
passing  through  the  pipes,  by  electric  currents  and  by  heat  from  coke, 
gas,  and  oil  fires;  these  methods  have  always  proved  inferior  to  steam. 

Thermometers  should  always  be  used,  for  the  manufacturer  who  heats 
his  fuel  accurately  and  uniformly  every  day  is  the  one  who  obtains  the 
greatest  efficiency  from  the  fuel  burned. 

SUPPLY  LINES 

Supply  lines  should  be  so  laid  as  to  insure  the  constant  circulation  of 
fuel  through  all  the  oil-supply  pipes  from  the  pump  to  the  burners.  A 
pressure  relief  valve  should  always  be  placed  at  the  farther  end  of  the 
burner  installation,  and  the  overflow  pipe  should  always  return  the  un- 
used fuel  to  the  supply  tank.  This  is  imperative  especially  when  using 
heavy  oils,  as  they  must  be  heated  to  reduce  their  viscosity.  Many 
people  have  put  in  a  large  oil  main  and  run  laterals  from  the  main  to  the 
boilers  or  furnaces.  Then  when  a  boiler  must  be  washed  out  or  a  furnace 
is  shut  down  for  repairs,  the  oil  solidifies  in  the  oil  pipe  or,  if  it  does  not 
solidify,  the  residuum  from  the  oil  collects  in  these  pipes,  causing  annoy- 
ance and  unnecessary  trouble.  The  locating  of  the  oil-storage  tank  and 
the  laying  out  of  the  pipe  lines  are  engineering  feats,  just  as  much  as  the 
equipment  of  the  boilers  or  furnaces. 

The  oil  pumps  should  be  brass  lined.  Two  should  always  be  provided, 
one  being  held  in  reserve  for  use  in  cases  of  any  emergency.  Air  chambers 


570  EFFICIENCY   IN   USE   OF   OIL  AS  FUEL 

and  pressure  gages  should  be  used;  the  former  to  reduce  the  pulsations 
caused  by  the  displacement  of  the  oil  by  the  piston  and  the  latter  to 
record  the  oil  pressure  maintained  upon  the  oil-supply  line.  The  spring 
of  the  pressure-relief  valve  should  be  very  sensitive,  in  order  that  it  may 
release  quickly  without  causing  a  variation  of  more  than  Y±  Ib.  (0.14  kg.) 
pressure  on  the  oil  supply  to  the  burners.  Oil  meters  should  be  used 
whenever  possible;  the  foreman  of  a  boiler  plant  or  furnace  department 
provided  with  these  instruments  is  encouraged  to  see  that  the  strictest 
economy  in  fuel  is  maintained. 

TYPES  OF  BURNERS  AND  THEIR  USE 

Numerous  oil  burners  are  on  the  market  but  the  three  types  most 
common  are:  The  external  atomizing  type,  which  is  largely  used  in  loco- 
motive and  stationary  boilers  and  in  large  furnaces;  the  internal  atomizing 
type,  which  is  chiefly  used  on  small  furnaces;  and  the  mechanical  type  of 
burner  used  on  ocean-going  vessels,  which  forces  the  oil  at  high  pressure 
through  a  small  aperture,  thus  making  a  funnel-shaped  flame.  This 
type  of  burner  is  used  on  ocean  vessels  because  no  steam  is  required  for 
atomizing,  consequently  there  is  no  loss  of  water.  This  saving  in  water, 
however,  is  accompanied  by  loss  in  fuel,  for  more  oil  is  required  to 
replace  a  ton  of  coal  while  using  a  mechanical  burner  than  with  the  exter- 
nal atomizing  burner,  because  a  mechanical  burner  cannot  atomize  the 
fuel.  For  example,  180  gal.  (681  1.)  of  oil  is  the  equivalent  of  a  long 
ton  of  coal  (calorific  value,  14,000  B.t.u.  per  Ib.)  when  using  a  mechanical 
burner;  while  with  the  use  of  an  atomizing  burner  only  147  gal.  of  oil  is 
the  equivalent. 

When  purchasing  atomizing  burners,  several  points  should  always  be 
considered. 

1.  The  burner  must  not  carbonize.     A  burner  that  carbonizes  should 
be  scrapped  at  once,  as  it  is  not  dependable,  is  wasteful  of  oil,  and  requires 
a  great  deal  of  care  and  attention.     Such  a  burner  reduces  the  burning 
of  oil  from  a  science  to  a  continuous  hazard  and  care. 

2.  The  oil  and  steam  orifices  should  be  independent  of  each  other  so 
that  excessive  oil  pressure  is  not  required  and  so  that  no  cutting  effect 
is  produced  when  burning  oil  containing  residuum  or  sand. 

3.  The  burner  should  be  so  constructed  and  filed  that  it  will  pro- 
duce a  flame  of  sufficient  length  and  width  to  fill  the  combustion  chamber 
of  the  furnace  or  firebox  of  boiler;  in  fact,  just  as  perfectly  as  a  drawer 
fits  into  its  opening  in  a  desk. 

4.  The  oil  orifice  should  be  large  enough  to  permit  free  exit  of  heavy 
oils  and  tars  therefrom,  and  the  atomizer  opening  should  be  as  small  as 
possible  in  order  to  reduce  to  a  minimum  the  amount  of  steam  or  com- 
pressed air  used  for  the  atomization  of  the  fuel. 


W.   N.  BEST  571 

For  boiler  equipments,  steam  is  preferable  as  an  atomizing  agent  if 
20  Ib.  (9  kg.)  pressure  or  more  is  carried  upon  the  boiler;  but  for  smaller 
pressures  air  should  be  used.  For  furnace  equipments,  air  is  preferable 
to  steam  for  atomizing  purposes  as  it  reduces  to  a  minimum  the  amount  of 
moisture  in  the  furnace. 

Today  boiler  settings  are  demanded  that  give  ample  room  for  com- 
bustion. Boilers  for  300  degrees  overload  are  being  set  with  a  distance  of 
14  ft.  (4.3  m.)  from  the  coal  stokers  to  the  elements  of  the  boiler.  When 
burning  oil,  the  larger  the  combustion  chamber  (up  to  a  certain  limit), 
the  greater  is  the  efficiency  obtained  from  the  fuel  and  the  higher  is  the 
boiler  horsepower  rating  obtained.  Recording  C02  instruments  should 
be  used  in  order  to  gage  the  air  supply  accurately  and  prevent  loss  of  fuel 
through  excessive  air  supply.  For  furnace  equipments,  pyrometers  are 
essential. 

Mexican  oil  is  high  in  sulfur,  often  containing  as  much  as  3.8  per  cent. 
It  is  therefore  necessary  that  a  combustion  chamber  be  used  on  furnaces 
so  that  the  atomized  oil  may  be  consumed  before  it  reaches  the  furnace 
proper.  In  boilers  there  is  no  difficulty  because  of  sulfur,  no  matter  of 
what  material  the  stock  is  made.  The  question  is  often  asked,  "Do  steel 
stacks  deteriorate  from  the  use  of  oil  containing  as  high  a  percentage  of 
sulfur  as  Mexican  oil?"  There  will  be  no  deterioration  unless  the  stack 
temperature  reaches  850°  F.  In  ordinary  boiler  practice,  there  is,  there- 
fore, no  likelihood  of  any  detrimental  effect  because  the  stack  temperatures 
do  not  reach  so  high  a  degree.  Many  people  condemn  the  use  of  this 
fuel  in  furnaces  because  their  furnaces  do  not  have  combustion  chambers 
to  consume  the  sulfur;  when  this  is  consumed  in  the  furnace,  there  is  a 
detrimental  effect  upon  the  metal  and  the  odor  in  the  shop  causes  the  men 
to  complain.  In  open-hearth  furnace  work,  it  has  been  found  good  prac- 
tice to  use  the  lighter  oils  until  the  charge  is  brought  down  and  is  covered 
with  slag,  after  which  the  Mexican  oil  can  be  used  with  no  detrimental 
effect  upon  the  metal. 

COST  OF  OPEKATING  WITH  OIL  AND  COAL 

Many  engineers  and  manufacturers  take  the  calorific  value  of  the  oil 
and  the  calorific  value  of  the  coal  as  bases  from  which  to  estimate  the 
difference  in  cost  of  operating  with  these  two  fuels.  This  should  not  be 
done  as  the  figures  thereby  obtained  are  incorrect. 

In  flue-welding  furnaces,  58  gal.  of  oil  is  the  equivalent  of  a  long  ton 
of  coal  (2240  Ib.)  due  to  the  fact  that  in  welding  with  coal,  for  safe- 
ending  the  flue,  it  is  necessary  to  coke  the  fire;  this  not  only  means  a  loss 
of  time  but  also  a  loss  of  the  volatile  hydrogen  and  hydrocarbon  gases, 
much  of  the  calorific  value  of  the  fuel.  These  gases  are  utilized  in  boiler 
practice;  here  the  economy  effected  depends  largely  on  the  size  of  the 


572  EFFICIENCY   IN   USE    OF  OIL  AS   FUEL 

plant,  for  one  man  can  fire  and  water-tend  a  battery  of  twelve  oil-fired 
boilers  almost  as  easily  as  he  can  care  for  one  boiler.  With  proper 
equipment,  the  tonnage  of  a  locomotive  is  increased  15  per  cent,  when 
changed  from  coal  to  oil. 

The  equivalent  of  one  long  ton  of  coal,  in  the  average  locomotive 
service,  is  180  gal.  oil;  in  the  average  stationary  boiler  practice, 
147  gal.;  in  forging  furnaces,  80  gal;  in  heat-treating  furnaces,  with  low 
temperatures,  80  gal.;  and  in  heat-treating  furnaces  with  high  tempera- 
tures and  annealing  furnaces,  63  gal.  In  working  these  figures,  it  must 
be  noted  that,  in  each  instance  quoted,  the  oil  has  a  calorific  value  of 
19,000  B.t.u.  per  Ib.  and  weighs  7J^  Ib.  per  gal.  while  the  coal  averages 
14,200  B.t.u.  per  Ib.  and  weighs  2240  Ib.  per  ton. 

3H  bbl.  oil  (42  gal.  per  bbl.)  is  the  equivalent  of  5000  Ib.  hickory  or 
4550  Ib.  white  oak. 

6  gal.  oil  equals  1000  cu.  ft.  of  natural  gas  of  calorific  value  of  1000 
B.t.u.  per  cu.  ft. 

3M  gal-  oil  equals  1000  cu.  ft.  of  commercial  or  water  gas  of  calorific 
value  of  620  B.t.u.  per  cu.  ft. 

2J4  gal.  oil  equals  1000  cu.  ft.  byproduct  coke-oven  gas  at  440  B.t.u. 
per  cu.  ft. 

0.4?  gal.  oil  equals  1000  cu.  ft.  blast-furnace  gas  at  90  B.t.u.  per  cu.  ft. 

Steel  works  are  now  utilizing  their  blast-furnace  gases,  which  are  of 
low  calorific  value,  being  on  an  average  but  90  B.t.u.  per  cu.  ft.  For  this 
reason,  it  is  customary,  when  these  gases  are  used  in  boilers,  large  furnaces, 
etc.,  to  use  an  auxiliary  fuel  in  combination  therewith.  This  auxiliary 
fuel  is  usually  coal  tar  (the  byproduct  of  coke  ovens);  this  makes  a 
fine  combination.  Usually  10  gal.  of  coal  tar  are  made  from  every  ton 
of  coal  coked  in  byproduct  coke  ovens;  this  tar  has  a  calorific  value  of 
162,000  B.t.u.  per  gal.  When  this  coal  tar  is  not  available,  crude  oil 
is  used. 

Efforts  have  been  made  in  West  Virginia  lately  to  retain  within  its 
border  all  the  natural  gas  produced  in  that  state.  If  those  fostering 
this  movement  succeed,  within  a  period  of  two  years  there  will  be  scarcely 
any  natural  gas  used  in  the  states  of  Indiana,  Ohio,  and  Pennsylvania. 
The  small  quantity  of  natural  gas  produced  in  these  three  states  will  be 
used  for  domestic  or  household  purposes,  rather  than  in  furnaces,  etc. 
Oil,  therefore*,  is  the  fuel  that  will  be  used  as  it  is  particularly  adapted  for 
furnaces  in  which  natural  gas  was  originally  used. 

DISCUSSION 

S.  0.  ANDROS,*  Chicago,  111. — The  most  important  thing  in  the  burn- 
ing of  fuel  oil  is  the  design  of  the  furnace.  Almost  any  of  the  good 
burners  on  the  market  will  be  efficient,  if  the  furnace  is  properly  designed. 

*  Editor,  OH  News. 


DISCUSSION  573 

Without  proper  furnace  design,  it  is  impossible  to  get  efficient  operation 
of  the  burner.  The  burner  itself  is  not  so  much  of  an  item  in  the  domestic 
field  as  the  assembling  of  the  system  for  domestic  use. 

RALPH  R.  MATTHEWS,*  Wood  River,  111. — In  1911,  when  connected 
with  the  Bureau  of  Mines,  I  inspected  various  installations  of  fuel  oil 
burners  in  Seattle,  Portland,  and  San  Francisco  and  found  that  every 
engineer  had  his  pet  type.  The  results  seemed  to  show  that  as  long  as 
the  oil  is  atomized  properly,  the  manner  in  which  it  is  atomized  is  not  of 
great  importance,  but  that  the  furnace  must  be  properly  designed. 
When  the  furnace  design  is  not  proper,  there  is  overheating  and  probably 
excessive  stack  temperature  due  to  burning  a  larger  quantity  of  fuel  oil 
than  should  be  necessary.  Conservation  of  fuel  oil  is  thus  closely  linked 
with  furnace  design. 

HENRY  P.  MUELLER,  f  St.  Louis,  Mo. — I  am  connected  with  a  bras 
foundry  that  makes  15  tons  of  metal  daily,  burning  1000  gal.  of  oil.  In 
the  last  ten  years  we  have  tried  practically  every  burner  on  the  market, 
but  the  most  satisfactory  was  one  we  designed.  The  oil  is  discharged 
as  a  spray  under  2^-lb.  pressure;  the  air  comes  out  of  the  lj^-in.  open- 
ing and  breaks  up  the  oil  at  the  end  of  the  burner,  throwing  it  18  in. 
before  it  enters  the  furnace. 

Some  of  our  burners  are  running  under  compressed  air,  which  in 
some  .cases  is  more  economical  than  steam.  The  oil  is  run  into  the 
tanks  under  air  pressure  and  is  left  in  circulation;  as  a  result,  it]  is 
unnecessary  to  clean  a  burner  or  pipe. 

The  furnace  is  of  the  revolving  type.  The  flame  does  not  come 
into  contact  with  the  metal;  instead  it  heats  the  top  of  the  furnace, 
then  as  that  is  revolved  under  the  charge,  the  metals  are  melted  with 
a  loss  of  only  1J^  per  cent. 

The  cost  of  melting  metal  on  a  normal  market  is  14  cents;  today 
we  are  paying  10  cents  per  gallon  for  oil  in  carload  lots,  therefore  the 
cost  of  melting  is  practically  doubled. 

JOHN  L.  HENNING,  Lake  Charles,  La. — In  burning  oil  we  have  not 
had  much  difficulty  in  getting  proper  atomization.  The  furnace  design 
is  the  most  important  thing.  We  used  a  common  burner  and  tried  to 
get  a  happy  medium  between  good  combustion  and  long  lived  furnace. 
We  burned  Mexican  oil  straight  without  any  trouble  with  that  type 
burner.  When  the  price  of  kerosene  was  low,  we  burned  it  in  the  same 
burners,  simply  letting  it  run  out,  and  got  as  good  combustion  as  with 
crude  oil  under  the  best  conditions. 


*  Chief  Chemist,  Roxana  Petroleum  Corpn. 
f  President,  Mueller  Brass  Foundry. 


574  EFFICIENCY   IN   USE    OF   OIL   AS   FUEL 

ARTHUR  KNAPP,  Shreveport,  La. — In  burning  oil  in  small  quantities 
it  is  necessary  to  remember  that  oil  must  be  brought  into  a  condition  to 
ignite;  that  is,  each  particle  must  be  vaporized  before  it  will  burn.  When 
burning  a  small  quantity,  as  trying  to  fire  a  10-hp.  boiler  or  smaller,  it 
is  necessary  to  have  a  large  surface  that  will  radiate  sufficient  heat  to 
vaporize  the  oil  and  ignite  the  vapor.  In  large  furnaces,  large  radiating 
surfaces  above  or  to  the  side  of  the  burner  furnish  the  required  heat. 

W.  N.  BEST  (author's  reply  to  discussion). — While  it  is  important 
to  have  the  furnace  properly  designed,  if  the  oil  burner  will  not  function 
with  the  furnace  design,  there  will  be  inefficient  combustion;  vice  versa, 
if  the  furnace  is  improperly  designed,  the  most  efficient  and  most  modern 
type  of  burner  will  be  a  failure. 

Mr.  Mathews  is  perfectly  correct  in  his  premises  of  a  proper  design 
of  furnace,  but  it  is  just  as  essential  to  have  a  burner  that  will  not 
carbonize;  that  will  atomize  any  gravity  of  liquid  fuel;  that  does  not  re- 
quire excessive  oil  pressure.  It  is  very  important,  in  burning  heavy  oil 
or  tars  to  use  low  oil  pressure.  Oil  or  tar  should  never  be  burned  under 
an  oil  or  tar  pressure  exceeding  12  lb.,  using  an  atomizing  burner. 

In  the  melting  of  brass  it  is  absolutely  essential  to  have  a  properly 
designed  furnace;  to  have  a  combustion  chamber  of  adequate  proportions 
to  insure  the  consumption  of  the  atomized  fuel  and  the  reduction  of  it 
to  heat  before  it  reaches  the  furnace  proper;  to  have  a  burner  that  will 
make  a  flame  to  fit  the  combustion  chamber  as  perfectly  as  a  drawer  fits 
an  opening  in  a  desk.  Without  the  combustion  chamber  the  furnace  will 
not  function  properly,  owing  to  the  fact  that  there  will  be  an  excessive 
amount  of  unmixed  air  entering  the  furnace,  which  will  result  in  an  exces- 
sive loss  of  metal. 


INDEX 


[NOTE. — In  this  Index  the  names  of  authors  of  papers  are  printed  in  small  capitals, 
and  the  titles  of  papers  in  italics.] 
Accumulation,  oil,  salt  domes,  Gulf  coastal  plain,  319. 
Alabama:  coal,  carbon  ratios,  141,  146. 
map,  geological,  141. 
oil  horizons,  143. 
oil  possibilities,  140. 
stratigraphy,  141. 
Alag6as,  Brazil,  oil-shale,  71. 
ALBERTSON,  M.:  Isostatic  Adjustments  on  a  Minor  Scale,  in  their  Relation  to  Oil 

Domes,  418. 

ALVEY,  GLENN  H.  and  FOSTER,  ALDEN  W.:  Barrel-day  Values,  412. 
AMBROSE,  A.  W. :  Analysis  of  Oil-field  Water  Problems,  245. 

Discussions:  on  Investigations  Concerning  Oil-water  Emulsion,  454. 

on  Value  of  American  Oil-shales,  235. 
Amortization:  definition,  374. 

oil  property  investment,  350. 
Analysis:  coal,  525. 

oil  and  gas  sands,  495. 
water  in  oil  wells,  253. 
Analysis  of  Oil-field  Water  Problems  (AMBROSE).  245;  Discussion:  (CONKLING),  265, 

267;  (DEGOLYER),  265,  266;  (REILLEY),  266;  (MILLS),  266,  267. 
ANDROS,  S.  O. :  Discussion  on  Efficiency  in  Use  of  Oil  as  Fuel,  572. 
Anglo-Persian  Oil  Co.,  9. 
Appalachian  oil  fields,  geology,  151. 
Application  of  Law  of  Equal  Expectations  to  Oil  Production  in  California  (BEAL  and 

NOLAN),  335. 
Application  of  Taxation  Regulations  to  Oil  and  Gas  Properties  (Cox),  374;  Discussion: 

(ARNOLD),  393. 

Appraisal,  oil  property,  method,  356. 

Appraisal  of  Oil  Properties  (OLIVER),  353;  Discussion:  (BEAL),  361;  (JOHNSON),  363. 
Argentina,  oil,  see  Oil,  Argentina. 
ARNOLD,  RALPH:  Discussions:  on  Application  of  Taxation  Regulations  to  Oil  and  Gas 

Properties,  393. 

on  Oil-shales  and  Petroleum  Prospects  in  Brazil,  76. 
on  Petroleum  Industry  of  Trinidad,  67,  68. 
on  Variation  in  Decline  Curves  of  Various  Oil  Pools,  373. 
ASHLEY,  G.  H. :  Discussions:  on  A  Resume  of  Pennsylvania-New  York  Oil  Field,  154. 

on  Water  Displacement  in  Oil  and  Gas  Sands,  501,  502. 
Asphalt,  related  hydrocarbons,  217. 
Asphaltenes  and  asphaltites,  definitions,  217. 

575 


576  INDEX 

Bahia,  Brazil,  oil-shale,  72. 

Baku  oil  fields:  casing  records,  464. 

drilling,  30,  459. 

production  technique,  31,  459. 

well  characteristics,  459,  460.     . 

yield,  33. 

Barrel-day  Values  (ALVEY  and  FOSTER),  412;  Discussion:  (JOHNSON),  416. 
Barrel-time  curves,  oil-well  depletion,  406. 
BASKERVILLE,  CHARLES:  Value  of  American  Oil-shales,  229. 
BATES,  Mo  WRY:  Discussion  on  Oil  Possibilities  in  Northern  Alabama,  150. 
BEAL,  CARL  H. :  Essential  Factors  in  Valuation  of  Oil  Properties,  344. 

Discussions:  on  Appraisal  of  Oil  Properties,  361. 

on  Variation  in  Decline  Curves  of  Various  Oil  Pools,  370. 
BEAL,  CARL  H.  and  NOLAN,  E.  D.:  Application  of  Law  of  Equal  Expectations  to  Oil 

Production  in  California,  335. 

BEST,  W.  N.:  Efficiency  in  Use  of  Oil  as  Fuel,  568;  Discussion,  574. 
Big  Sinking  oil  pool,  Kentucky,  168. 
Biography,  Anthony  F.  Lucas  (GOODRICH),  421. 
Bitumen:  definition,  217. 

derivatives,  217. 

Philippines,  54. 

Bottom  settlings,  oil  wells,  definition,  430,  458. 
BOWNOCKER,  J.  A. :  Rise  and  Decline  in  Production  of  Petroleum  in  Ohio  and  Indiana, 

108. 

BRADLEY,  OLIVER  U. :  Valuation  Factors  of  Casing-head  Gas  Industry,  395. 
BRANNER,  J.  C. :  Discussion  on  Oil-shales  and  Petroleum  Prospects  in  Brazil,  76. 
Brazil:  oil,  69,  76. 

oil-shales,  69. 

petroliferous  rocks,  241. 
Brines:  oil-field,  origin,  269,  282. 

solubility  of  gypsum,  273. 

solubility  of  limestone,  275. 
B.  S.,  definition,  430,  458. 

photomicrographs,  433,  434,  436. 

water  content,  438,  458. 
Burners,  oil,  570. 

California,  oil,  production  curves,  335,  339. 

Carbon  ratios,  coal,  525. 

Carbon  Ratios  of  Coals  in  West  Virginia  Oil  Fields  (REGER),  522,  Discussion:  (SiNGE- 

WALD),  526. 

Carbonaceous  matter  in  oil-forming  rocks,  177. 

Carbonization  state  of  organic  matter  in  oil-bearing  formations,  179. 
Casing-head  gas :  composition,  397. 

contracts  for  purchase,  400. 

efficiency  of  plant,  399. 

estimate  of  costs,  400. 

investment  value,  395. 

market  quotations,  404. 

oil-lease  connection,  398. 

plant  efficiency,  399. 

plant  location,  398. 

price  schedule,  492. 


INDEX  577 

Casing-head  gas:  quality,  397. 

quantity  available,  396. 
valuation  factors,  395. 
Casing-head  gasoline,  importance,  395. 
Casing  records,  Baku  oil  fields,  464. 
Cement  oil  field,  Oklahoma:  comparison  with  other  fields,  160. 

Cyril  gypsum  bed,  158. 

deep  sands,  positions,  161. 

geological  structure,  159. 

history  of  development,  157. 

stratigraphy,  158. 

topography ,  156. 
CLAPP,  FREDERICK  G.:  Geology  of  Cement  Oil  Field,  156. 

Discussion  on  Secondary  Intrusive  Origin  of  Gulf  Coastal  Plain  Salt  Domes,  324. 
Classification:  oil,  505. 

rock,  oil  drilling,  424,  428. 
Climatic  factor  in  origin  of  oil,  212. 
Clinton  sand  fields,  Ohio,  petroleum,  113,  119. 
Coal:  Alabama,  carbon  ratios,  141,  146. 

analyses  and  carbon  ratios,  525. 

carbon  ratios,  522,  525. 

cost,  compared  with  oil,  571. 

distillation,  products,  219,  224. 

formation,  theory,  221,  224. 

insoluble  portions,  relations,  221. 

nature,  217,  221. 

prices,  comparison  with  oil  prices,  553. 

soluble  portions,  relations,  219. 
Cobalt,  Ont.,  dome  formation  in  lake,  418. 

COLLOM,  R.  E. :  Discussion  on  Investigations  Concerning  Oil-water  Emulsion,  458. 
Comodoro  Rivadavia  oil  field,  42. 
Composition  of  Petroleum  and  its  Relation  to  Industrial  Use  (MABERY),  505;  Discussion: 

(SADTLER),  518;  (TILLSON),  520;  (MABERY),  521. 
CONKLING,  R.  A. :  Discussions:  on  Analysis  of  Oil-field  Water  Problems,  265,  267. 

on  Industrial  Representation  in  the  Standard  Oil  Co.  (N.  /.),  239. 

on  Oil-field  Brines,  290. 

on  Petroleum  Industry  of  Trinidad,  68. 
Corniferous  limestone,  Indiana,  petroleum,  115. 
COSTE,  EUGENE  :  Discussion  on  Secondary  Intrusive  Origin  of  Gulf  Coastal  Plain  Salt 

Domes,  322. 
Costs:  fuel,  coal  and  oil,  571. 

oil:  American  and  Mexican  fields,  554. 

transportation,  Mexican,  539. 
COTTRELL,  F.  G.:  Discussion  on  Investigations  Concerning  Oil-water  Emulsion,  455, 

456. 

Cox,  THOMAS:  Application  of  Taxation  Regulations  to  Oil  and  Gas  Properties,  374. 
Cyril  gypsum  bed,  Oklahoma,  158. 

Decline  curves,  oil  fields,  variation,  365. 

Deductions,  oil  and  gas  property  taxation,  375. 

DEGOLYER,  E.:  Discussions:  on  Analysis  of  Oil-field  Water  Problems,  265,  266. 

on  Nature  of  Coal,  223. 

on  Oil-field  Brines,  287,  288. 

37 


578  INDEX 

DEGOLYBR,  E. :  on  Oil  Fields  of  Persia,  15. 

on  Petroleum  Industry  of  Trinidad,  67,  68. 

on  Petroleum  in  the  Argentine  Republic,  44. 

on  Secondary  Intrusive  Origin  of  Gulf  Coastal  Plain  Salt  Domes,  325. 
Demulsification,  oil,  electrical,  456. 

DE  OLIVEIRA,  EUZEBIO  P.:  Petroliferous  Rocks  in  Serra  de  Baliza,  241. 
Depletion:  computation,  oil  and  gas  properties,  382. 

oil  wells,  curves,  405. 
Deposition,  oil,  conditions,  194. 
Depreciation,  definition,  374. 
Determination  of  Pore  Space  of  Oil  and  Gas  Sands  (MELCHER),  469;  Discussion: 

(MILLS),  490,  491;  (SMALL),  490;  (WASHBURNE),  497. 
Diasphaltenes,  definition,  217. 

Displacement  of  water  in  oil  and  gas  sands,  498,  499. 
Distillation:  coal,  products,  219,  224. 

oil-shales,  outline,  230. 

Dollar-time  curves,  oil-well  depletion,  405,  406,  407. 
Domes:  formation  in  Cobalt  Lake,  418. 

oil,  formation,  418. 

salt,  see  Salt  domes. 
Drilling,  oil:  Appalachian  field,  153. 

Baku  fields,  459. 

rock  classification,  424,  428. 

Russia,  30,  37,  38. 

Russian  machinery,  462,  463. 

Trinidad,  62. 
Drilling  and  Production  Technique  in  the  Baku  Oil  Fields  (KNAPP),  459;  Discussion: 

(KNAPP),  466. 

Dryness,  oil  strata,  498,  501. 
DUCE,  J.  F. :  Discussion  on  Genetic  Problems  Affecting  Search  for  New  Oil  Regions,  197. 

Efficiency  in  Use  of  Oil  as  Fuel  (BEST),  568;  Discussion:  (ANDROS),   572;   (MAT- 
THEWS), 573;  (MUELLER),  573;  (HENNING),  573;  (KNAPP),  574,  (BEST),  574. 
Electrical  demulsification,  oil,  456. 
Employees'  conferences,  Standard  Oil  Co.,  238. 
Employees'  insurance,  240. 
Emulsion,  oil-water,  see  Oil-water  emulsion. 
Equal  expectations,  law,  oil  production,  335. 
Essential  Factors  in  Valuation  of  Oil  Properties  (BEAL),  344. 
Exports,  Mexican  petroleum,  532,  533. 

Family  curve,  oil-well  production,  335,  343. 
Folding  of  strata,  oil  genesis,  182. 

Foreign  Oil  Supply  for  the  United  States  (SMITH),  89;  Discussion:  (REQOA),  93;  (WASH- 
BURNE), 94;  (JOHNSTON),  95. 
FOSTER,  ALDEN  W.  and  ALVEY,  GLENN  H.:  Barrel-day  Values,  412. 

GARFIAS,  V.  R. :  General  Notes  on  the  Production,  Marine  Transportation,  and  Taxation 

of  Mexican  Petroleums,  528. 
Gas:  casing-head,  see  Casing-head  gas. 
helium  content,  503,  504. 
movement:  Louisiana,  502. 
McKeesport  gas  pool,  501. 


INDEX  579 

Gas:  sands,  see  Oil  and  gas  sands. 

wells,  depletion,  computation,  384. 
Gasoline:  natural-gas,  Pennsylvania,  153. 

production,  513. 

use,  513. 
General  Notes  on  the  Production,  Marine  Transportation,  and  Taxation  of  Mexican 

Petroleums  (GARFIAS),  528. 
Genesis,  oil:  carbonaceous  matter  in  the  oil-forming  rocks,  177. 

deposition  conditions,  194. 

folding  of  strata,  182. 

state  of  carbonization  of  organic  matter  in  oil-bearing  formations,  179. 

thickness  of  sedimentary  formations,  192. 
Genetic  Problems  Affecting  Search  for  New  Oil  Regions  (WHITE),   176;  Discussion: 

(JOHNSON),  195;  (HIXON),  195,  197;  (REGER),  196,  197;  (Dues),  197. 
Geology,  oil:  Alabama,  141. 

Cement  field,  Oklahoma,  156. 

Irvine  district,  Kentucky,  165. 

Kansas,  100. 

Kentucky,  127. 

Pennsylvania-New  York  field,  151. 

Persia,  11. 

Philippines,  48. 

Russia,  21. 

Tennessee,  123. 

Trinidad,  60. 

Geology  of  Cement  Oil  Field  (CLAPP),  156. 
GLENN,  L.  C.:  Oil  Fields  of  Kentucky  and  Tennessee,  122. 
GOODRICH,  H.  B.:  Biography  of  Anthony  F.  Lucas,  421. 
Great  Britain,  oil  resources,  3. 
Gulf  coastal  plain,  salt  domes,  origin,  295. 
Gypsum:  origin  in  Red  Beds,  274. 

origin  in  salt  domes,  272,  285. 

solubility  in  sodium  chloride  solutions,  273. 

HACKFORD,  F.  E.:  Nature  of  Coal,  217. 
Hardstoft  oil  wells,  Great  Britain,  5. 
Hartselle  sandstone,  Alabama,  oil  possibilities,  144,  150. 
Helium,  presence  in  natural  gas,  503,  504. 

HENNING,  JOHN  L.:  Discussion  on  Efficiency  in  Use  of  Oil  as  Fuel,  573. 
HEROLD,  STANLEY  C.:  Petroleum  in  the  Argentine  Republic,  40;  Discussion,  45. 
HICKS,  CLARENCE  J.:  Industrial  Representation  in  the  Standard  Oil  Co.  (N.  /.),  237. 
HEXON,  H.  W. :  Discussions:  on  Genetic  Problems  Affecting  Search  for  New  Oil  Regions, 
195,  197. 

on  Secondary  Intrusive  Origin  of  Gulf  Coastal  Plain  Salt  Domes,  329. 

on  Water  Displacement  in  Oil  and  Gas  Sands,  503. 
HUNTER,  CAMPBELL  M.:  Oil  Fields  of  Persia,  8. 
HUNTLEY,  STIRLING  and  JOHNSON,  ROSWELL  H.:  A  Resume  of  Pennsylvania-New 

York  Oil  Field,  151. 
Hydrocarbons:  oil  components,  506. 

petroliferous,  217. 

Indiana,  petroleum,  production  rise  and  decline,  110. 

Industrial  Representation  in  the  Standard  Oil  Co.  (N.  J.)  (HICKS),  237;  Discussion: 
(CONKLING),  239;  (PRATT),  240. 


580  INDEX 

Insurance,  employees',  240. 

International  Aspects  of  the  Petroleum  Industry  (MANNING),  78;  Discussion:  (WALDO), 

87. 

Investigations  Concerning  Oil-water  Emulsion  (McCoy,  SHIDEL  and  TRAGER),  430; 
Discussion:  (AMBROSE),  454;  (TRAGER),  454,  455,  456,  457;  (MOORE), 
454,  455,  457;  (WASHBURNE),  455,  457;  (COTTRELL),  455,  456:  (COLLOM), 
458. 

Irvine  Oil  District,  Kentucky  (ST.  CLAIR),  165. 
Irvine  oil  district,  Kentucky:  Big  Sinking  pool,  168. 
economic  conditions,  172. 
extension  of  eastern  fields,  169. 
geology,  165. 
location,  165. 
map,  171. 

occurrence  of  oil,  167. 
Isocarb:  definition,  147,  522. 
West  Virginia,  147,  522. 

Isostatic  Adjustments  on  a  Minor  Scale,  in  their  Relation  to  Oil  Domes  (ALBERTSON), 
418. 

JOHNSON,  ROSWELL  H.:  Variation  in  Decline  Curves  of  Various  Oil  Pools,  365;  Discus- 
sion, 373. 

Water  Displacement  in  Oil  and  Gas  Sands,  498. 
Discussions:  on  Appraisal  of  Oil  Properties,  363. 
on  Barrel-day  Values,  416. 

on  Genetic  Problems  Affecting  Search  for  New  Oil  Regions,  195. 
on  Modified  Oil-well  Depletion  Curves,  411. 
on  Water  Displacement  in  Oil  and  Gas  Sands,  502,  503. 
JOHNSON,  ROSWELL  H.  and  HUNTLEY,  STIRLING:  A  Resume  of  Pennsylvania-New 

York  Oil  Field,  151. 
JOHNSTON,  R.  H.:  Discussion  on  a  Foreign  Oil  Supply  for  the  United  States,  95. 

KANSAS:  oil,  see  Oil,  Kansas. 

Pennsylvanian  rocks,  divisions,  102. 

Permian  rocks,  divisions,  104. 

stratigraphy,  100. 
Kentucky:  oil,  Irvine  district,  165. 

oil  fields,  124. 
Kerites:  definitions,  218. 

soluble,  relations  with  soluble  portions  of  coal,  219. 
Kerotenes,  kerols,  keroles,  and  kerites,  definitions,  218. 
KNAPP,  ARTHUR:  Drilling  and  Production  Technique  in  the  Baku  Oil  Fields,  459. 

Modified  Oil-well  Depletion  Curves,  405. 

Rock  Classification  from  the  Oil-driller's  Standpoint,  424. 

Discussions:  on  Efficiency  in  Use  of  Oil  as  Fuel,  574. 
on  Oil  Fields  of  Russia,  37. 
on  Petroleum  Industry  of  Trinidad,  68. 

KNAPP,  I.  N. :  Discussion  on  Drilling  and  Production  Technique  in  the  Baku  Oil  Fields, 
466. 

Labor  policy,  Standard  Oil  Co.,  237. 

Law  of  equal  expectations,  oil  production,  335. 

Lease  status-time  curves,  oil-well  depletion,  405,  406,  407. 


INDEX  581 

Limestone  caps,  origin,  274,  285. 

Limestone:  solubility  in  sodium  chloride  solutions,  275. 

solution  and  deposition  in  sands,  276. 
Lubricants:  production,  514. 

use,  514,  520. 

viscosity  and  quality,  520,  521. 
Lucas,  Anthony  F.,  biography,  421. 

MABERY,  CHARLES  F. :  Composition  of  Petroleum  and  its  Relation  to  Industrial  Use 

505;  Discussion,  521. 

MACREADY,  GEORGE  A. :  Petroleum  Industry  of  Trinidad,  58. 
MADGWICK,  T.  G.  and  THOMPSON,  A.  BEEBY:  Oil  Fields  of  Russia,  17. 
MANNING,  VAN  H.:  International  Aspects  of  the  Petroleum  Industry,  78. 
Map:  Alabama,  geological,  141. 

Irvine  oil  district,  Kentucky,  171. 

Mid-Continent  oil  field,  98. 

North  American  petroliferous  provinces,  202. 

Ohio,  oilfields,  116. 

Persia,  oil  fields,  10. 

Trinidad,  oil  fields,  59. 
Maranhao,  Brazil,  oil-shale,  70. 
Marine  origin  of  oil,  208. 
MATTESON,  W.  G. :  Secondary  Intrusive  Origin  of  Gulf  Coastal  Plain  Salt  Domes,  295 

Discussion,  327,  331. 

MATTHEWS,  RALPH  R. :  Discussion  on  Efficiency  in  Use  of  Oil  as  Fuel,  573. 
McCoY,  ALEX.  W.,  SHIDEL,  H.  R.  and  TRACER,  E.  A.:  Investigations  Concerning 

Oil-water  Emulsion,  430. 
McKeesport  gas  pool,  gas  movement,  501. 

MELCHER,  A.  F. :  Determination  of  Pore  Space  of  Oil  and  Gas  Sands,  469. 
Mexico:  distance  to  American  ports,  541. 

foreign  oil  companies,  530. 

measurement  of  petroleum,  531. 

oil,  see  Oil,  Mexico. 

taxation,  see  Oil,  Mexico,  taxation. 

units  of  measurement,  531. 
Mid-Continent  oil  field,  map,  98. 
MILLS,  R.  VAN  A. :  Discussions:  on  Analysis  of  Oil-field  Water  Problems,  266,  267. 

on  Determination  of  Pore  Space  of  Oil  and  Gas  Sands,  490,  491. 

on  Oil-field  Brines,  281,  286,  288,  289,  290. 

on  Petroleum  Industry  of  Trinidad,  67. 

on  Secondary  Intrusive  Origin  of  Gulf  Coastal  Plain  Salt  Domes,  329. 
Modified  Oil-well  Depletion  Curves  (KNAPP),  405;  Discussion:  (JOHNSON),  411. 
MOORE,  RAYMOND  C. :  Petroleum  Resources  of  Kansas,  97. 
MOORE,  R.  W. :  Discussion  on  Investigations  Concerning  Oil-water  Emulsion,  454,, 

455,  457. 

Movement  of  oil,  water,  and  gas  in  displacement,  499. 
MUELLER,  HENRY  P.:  Discussion  on  Efficiency  in  Use  of  Oil  as  Fuel,  573. 

National  Petroleum  Co.,  Philippines,  49. 

Natural  gas,  Pennsylvania,  153. 

Natural-gas  gasoline,  Pennsylvania,  153. 

Nature    of    Coal     (HACKFORD),  217;  Discussion:  (PRATT),     223;     (WHITE), 

(DEGOLYER),  223;  (THIESSEN),  224;  (WATERS),  227. 
NELSON,  WILBUR  A.  N. :    Discussion  on  Oil  Fields   of  Kentucky  and  Tennessee,  134 


582  INDEX 

New  York,  oil,  151. 

NOLAN,  E.  D.  and  BEAL,  CARL  H.:  Application  of  Law  of  Equal  Expectation*  to  Oil 

Production  in  California,  335. 
North  America,  map,  petroliferous  provinces,  202. 
North  Argentine-Bolivian  oil  field,  summary,  40. 

Ohio:  map,  oil  fields,  116. 
oil:  composition,  511. 

production  rise  and  decline,  110. 

Oil:  accumulation,  salt  domes,  Gulf  coastal  plain,  319. 
Alabama:  development,  148. 

future  prospecting,  149. 

geology,  141. 

Hartselle  sandstone,  144,  150. 

horizons,  143. 

possibilities,  140. 

structural  features,  146. 
Anglo-Persian  Oil  Co.,  9. 
Argentina:  Comodoro  Rivadavia  district,  42. 

Gallegos-Punta  region,  44. 

Government  reservations,  45. 

localities,  40. 

Mendoza  and  Neuquen  provinces,  41. 

North  Argentine-Bolivian  field,  40. 

Salta-Jujuy  district,  41. 
atomizing  burners,  570. 
Baku  fields,  30,  31,  33,  459. 
Big  Sinking  pool,  Kentucky,  168. 
Brazil,  69,  76,  242. 
burners,  570. 

Carboniferous  strata,  201. 
classification,  505. 
climatic  factor  in  origin,  212. 
commercial  products,  preparation,  512. 
components:  hydrocarbons:  aromatic,  508. 
basic  series,  506. 
ethylene  series,  507. 
methane  series,  506. 

nitrogen  bases,  509. 

oxygen  compounds,  508. 

sulfur,  509. 
composition,  505. 
consumption,  U.  S.,  78,  82. 
cost,  compared  with  coal,  571. 
costs,  Mexican  and  American  fields,  554. 
demulsification,  electrical,  456. 
deposition,  conditions,  194. 
displacement  of  water  in  rock,  499. 
drilling,  see  Drilling,  oil. 
efficiency  in  use,  568. 
emulsified,  see  Oil-water  emulsion. 
exclusion  of  Americans  from  foreign  fields,  85. 
family  curve,  production,  335,  343. 


INDEX  583 


Oil:  foreign  sources  of  supply,  84. 

formation  in  shale  by  pressure,  223. 

future  supply,  89,  92. 

gasoline  production  and  use,  513. 

genesis,  see  Genesis,  oil. 

geology,  see  Geology,  oil. 

Great  Britain:  future  prospects,  4. 

government  regulations,  3. 

Hardstoft  wells,  5. 

political  considerations,  3. 

Scottish  wells,  5. 

Hardstoft  wells,  Great  Britain,  5. 
importance,  79. 
Indiana:  Corniferous  limestone,  115. 

history  of  development,  108. 

production,  109. 

rocks,  109. 

sandstones,  115. 

Trenton  limestone,  109. 

well  records,  112. 
industry,  79. 
international  aspects,  78. 
Irvine  district,  Kentucky,  165. 
Kansas:  districts,  97. 

future  possibilities,  106. 

geologic  section,  101. 

history,  97. 

map  of  Mid-Continent  field,  98. 

production,  99,  105. 

stratigraphy,  100. 

technology,  105. 
Kentucky:  districts,  124. 

future  possibilities,  132,  133,  138. 

geology,  127. 

history  of  development,  125. 

Onondaga  limestone  accumulation,  137. 

Paint  Creek  Dome,  133. 

structure  in  relation  to  occurrence,  129. 

technology,  130. 
law  of  equal  expectations,  335. 
losses,  245. 

lubricant,  production  and  use,  514,  520. 
manifestations,  Russia,  20. 
map,  North  American  provinces,  202. 
marine  origin,  208. 
Mexico:  companies,  538. 

costs,  operation,  554. 

destinations,  537. 

development,  528. 

exports,  532,  533. 

foreign  companies,  530. 

grades,  539,  547. 

measurement,  531. 


584  INDEX 

Oil:  Mexico:  operating  costs,  554. 
prices,  550. 
production,  532,  536. 
production  per  well,  529. 
statistics,  532. 
tank  steamers,  535. 
taxation:  controversies,  557. 
export  stamp  tax,  546,  548. 
former,  545. 
grades,  547. 
recent,  546. 

relation  with  oil-coal  prices,  555. 
stamp  tax,  546,  548. 

transportation:  capacity  of  steamers,  540. 
cost  of  steamers,  542. 
costs,  539,  543. 

distance  to  American  ports,  541. 
tank  steamers,  540. 
value,  550. 

Mid-Continent  field,  map,  98. 
movement  in  displacement  of  water  in  rock,  499. 
necessity,  78,  90. 

new  regions,  genetic  problems  affecting  search,  176. 
New  York:  future  possibilities,  154. 
geology,  151. 
grade,  152. 

North  America,  map  of  provinces,  202. 
Ohio:  Clinton  sand  fields,  113,  119. 
composition,  511. 
history  of  development,  108. 
production,  109. 
rocks,  109. 
sandstones,  115. 
Trenton  limestone,  109. 
well  records,  112. 
organic  origin,  207. 
origin,  199,  204,  207. 
Paleozoic  strata,  200. 
Pennsylvania:  drilling,  153. 
future  possibilities,  154. 
geology,  151. 
grade,  152. 
history,  151. 

Persia:  Anglo-Persian  Oil  Co.,  9. 
geology,  11. 

history  of  development,  8. 
map  of  fields,  10. 
occurrence,  8. 
production,  15. 
technology,  14. 

Philippines :  history  of  development,  49. 
National  Petroleum  Co.,  49. 
properties,  53. 


INDEX  585 


Oil:  Philippines:  stratigraphy,  48. 

prices :  comparison  with  coal  prices,  553. 

future,  347. 

Mexican  and  American,  552. 
production:  U.  S.,  82,  232,  532. 

world's,  532. 

production  methods,  Baku,  31. 
provinces,  199,  205,  215. 
refining,  method,  512. 
requirements,  U.  S.,  232. 
resources,  world's,  81. 
scientific  work,  value,  517. 
Scotland,  5. 

segregation  above  water,  279. 
sources,  199,  204,  207,  517. 
substitutes,  83. 
sulfur  content,  509. 
supply:  foreign,  84,  89. 

future,  89,  92. 
supply  lines,  569. 

taxation,  relation  with  oil-coal  prices,  555. 
temperature  in  use,  569. 
Tennessee:  geology,  123. 

history,  122. 
transportation:  costs,  539. 

Mexico,  539. 
Trinidad:  character,  63. 

drilling,  62. 

future  possibilities,  64. 

geology,  60. 

map  of  fields,  59. 

occurrence,  61. 

production,  60,  63. 

technology,  62. 

transportation,  64. 
use:  burners,  570. 

cost,  571. 

efficiency,  568. 

furnace  design,  572,  574. 

supply  lines,  569. 

temperature,  569. 
uses,  80. 

value  of  American  shales,  229. 
West  Virginia,  limits,  524. 
world's  production,  532. 
Oil  and  gas  areas,  West  Virginia,  523. 

Oil  and  gas  properties,  taxation,  see  Taxation^  oil  and  gas  properties. 
Oil  and  gas  sands :  analyses,  495. 
dryness,  498,  501. 
migration  of  oil  and  water,  492. 
pore  space,  see  Pore  space,  oil  and  gas  sands. 
water  displacement,  498. 
Oil  companies,  Mexico,  538. 


586  INDEX 

Oil  drilling,  see  Drilling,  oil. 
Oil-field  brines,  origin,  269,  282. 

Oil-field  Brines  (WASHBURNE),  269;  Discussion:  (MILLS),  281,  286,  288,  289,  290; 
(DEGOLYER),  287,  288;  (PRATT),  289;  (CONKLING),  290;  (WASHBURNE), 
290. 

Oil-field  water  problem:  data  for  analysis,  248. 
field  tests,  252. 
maps  and  cross-sections,  249. 
Oil  fields:  Appalachian,  geology,  151. 
appraisal,  344,  353. 
decline  curves,  variation,  365. 
fraudulent  stock  promotion,  354. 
Mexico,  development,  528. 
Mid-Continent,  map,  98. 
Ohio,  map,  116. 

Oklahoma,  cement  field,  geology,  156. 
Russia:  Baku  fields,  30,  31,  33. 
disposal  of  oil,  19. 
drilling,  30,  37,  38. 
geology,  21. 
history,  17. 
leasing,  19. 

manifestations  of  oil,  20. 
oil  occurrence,  26. 
production,  33,  37. 
production  methods,  31. 
relative  importance,  36. 
stratigraphy,  21. 
structure,  25. 
yields,  33,  37. 
speculation,  353. 
Trinidad,  58. 

valuation,  factors  influencing,  344,  359. 
value,  353,  355. 

Oil  Fields  of  Kentucky  and  Tennessee  (GLENN),  122;  Discussion:  (SEARS),  133;  (NEL- 
SON), 134;  (ST.  GLAIR),  137. 

Oil  Fields  of  Persia  (HUNTER),  8;  Discussion:  (DEGOLYER),  15;  (WHITE),  16. 
OU  Fields  of  Russia  (THOMPSON  and  MADGWICK),   17;  Discussion:  (KNAPP),  37; 

(THOMPSON),  38. 
Oil  Possibilities  in  Northern  Alabama  (SEMMES),   140;  Discussion:  (WHITE),   150; 

(BATES),  150. 

Oil  properties,  valuation,  see  Valuation,  oil  properties. 
Oil-shales:  American,  value,  229. 
Brazil:  Alag6as,  71. 
Bahia,  72. 
Maranhao,  70. 
Sao  Paulo,  74. 
southern  Brazil,  74. 
caking  and  non-caking,  231. 
characteristics,  231. 
definition,  229. 
distillation,  outline,  230. 
industry,  present  development,  83. 


INDEX  587 

Oil-shales:  nature,  226. 

requirements  for  economic  value,  230. 
treatment:  American,  231. 

history,  229. 

Scotch,  233. 

yield  for  a  productive  field,  209. 
Oil-shales  and  Petroleum  Prospects  in  Brazil  (WILLIAMS),  69;  Discussion:  (ARNOLD), 

76;  (WHITE),  76;  (THOMAS),  76;  (BRANNBR),  76. 
Oil  strata,  dryness,  498,  501. 

Oil- water  emulsion :  bottom  settlings,  430,  438,  458. 
B.  S.,  definition,  430,  458. 
bubbles,  431. 
classes,  437. 
definition,  433. 
distillation  results,  441. 
electrical  treatment,  455,  456. 
investigations:  apparatus,  439. 

field,  441. 

laboratory,  430. 
permanent,  437. 

photomicrograph,  431,  432,  435. 
physico-chemical  properties,  437. 
production  diagrams,  444. 
size  of  bubbles,  431. 
water  content,  438,  458. 
Oil-well  depletion  curves,  405. 
Oil  wells:  bottom  settlings,  definition,  430,  458. 
buckets,  diagram,  443. 
depletion,  computation,  382. 
diagram,  working  parts,  442. 
erratic,  341. 

family  curve,  production,  335,  343. 
future  production :  curves,  338,  340. 

estimation,  342. 
law  of  equal  expectations,  335. 
life,  determination,  340. 
persistence,  372,  373. 

production  curves,  335,  338,  340,  341,  365. 
production  diagrams,  oil-water  emulsion,  444. 
production  during  decline,  365. 
productivity,  pore  space  effect,  479. 
water:  analysis,  253. 

analysis  of  problems,  data,  248. 

bottom,  263,  265. 

correction,  262. 

detectors,  256. 

edge,  264. 

effect  on  production,  246. 

field  tests,  252.    • 

intermediate,  263. 

maps  and  cross-sections,  249. 

objections,  246. 

production  diagrams,  444. 


588  INDEX 

OH  wells:  water:  sources,  246,  259,  267. 
top,  262. 

working  parts,  diagram,  442. 
Oklahoma:  Cement  oil  field,  see  Cement  oil  field,  Oklahoma. 

Cyril  gypsum  bed,  158. 

OLIVER,  EARL:  Appraisal  of  Oil  Properties,  353. 
Onondaga  limestone  oil  formation,  Kentucky,  137. 
Organic  origin  of  oil,  207. 
Origin:  coal,  221,  224. 

gypsum  in  Red  Beds,  274. 

gypsum  in  salt  domes,  272,  285. 

limestone  caps,  274,  285. 

oil,  199,  204,  207. 

oil-field  brines,  269,  282. 

peat,  224. 

salt  cores,  270,  285. 

salt  domes,  Gulf  coastal  plain,  see  Salt  domes,  Gulf  coastal  plain,  origin. 

PAIGE,  SIDNEY:  Discussion  on  Water  Displacement  in  Oil  and  Gas  Sands,  501,  502. 

Paint  Creek  oil  dome,  Kentucky,  133. 

PANYITY,  L.  S. :  Discussion  on  Rise  and  Decline  in  Production  of  Petroleum  in  Ohio 

and  Indiana,  119. 

PEARSE,  ARTHUR  L.:  Discussion  on  Value  of  American  Oil-shales,  233. 
Peat,  origin,  224. 
Pennsylvania:  natural  gas,  153. 

natural-gas  gasoline,  153. 

oil,  151. 

PERRINE,  IRVING:  Discussion  on  Petroliferous  Provinces,  216. 
Persia:  map,  10. 

oil,  see  Oil,  Persia. 
Petroleum  Industry  of  Trinidad  (MACREADY),   58;  Discussion:   (ARNOLD),  67,   68; 

(DEGOLYER),  67,  68;  (MILLS),  67;  (CONKLING),  68;  (KNAPP),  68. 
Petroleum  in  the  Argentine  Republic  (HEROLD),  40;  Discussion:  (DEGOLYER),  44; 

(HEROLD),  45. 

Petroleum  in  the  Philippines  (SMITH),  47;  Discussion:  (PRATT),  54;  (WHITE),  56. 
Petroleum  Resources  of  Great  Britain  (VEATCH),  3;  Discussion:  (WASHBURNE),  6. 
Petroleum  Resources  of  Kansas  (MOORE),  97. 
Petroliferous  hydrocarbons,  217. 
Petroliferous  Provinces  (WOODRUFF),  199;  Discussion:  (SCHUBERT),  204;   (PERRINE), 

216;  (WASHBURNE),  216. 

Petroliferous  Rocks  in  Serra  da  Baliza  (DE  OLIVEIRA),  241. 
Philippines:  bitumens,  54. 

correlation  of  Far  Eastern  Tertiary,  51. 

National  Petroleum  Co.,  49. 

oil,  47. 

stratigraphy,  48. 
Photomicrographs:  bottom  settlings,  oil,  433,  434,  436. 

oil-water  emulsion,  431,  432,  435. 
POGUE,  JOSEPH  E. :  Discussion  on  Secondary  Intrusive  Origin  [of  Gulf  Coastal  Plain 

Salt  Domes,  324. 
Pore  space:  building  stones,  477. 

oil  and  gas  sands :  data,  482. 

determination:  dipping  in  paraffin,  470. 


INDEX  589 

Pore  space:  oil  and  gas  sands:  determination:  methods,  469. 
paraffin  method,  470. 
pycnometers,  473. 
results,  478,  480. 
small  samples,  474. 
volume  of  individual  grains,  472. 
volume  of  sample  by  weighing,  472. 
water  absorption  method,  477. 
nature,  469. 

relation  to  productivity,  479. 
water  absorption,  477. 

Porosity,  oil  and  gas  sands,  see  Pore  space,  oil  and  gas  sands. 
PRATT,  W.  E.:   Discussions:   on  Industrial  Representation  in  the  Standard  Oil  Co. 

(N.  /.),  240. 
on  Nature  of  Coal,  223. 
on  Oil-field  Brines,  289. 
on  Petroleum  in  the  Philippines,  54, 
Price,  future,  oil,  347. 
Prices,  oil  and  coal,  comparison,  553. 
Proceedings,  St.  Louis  meeting,  1920,  v. 
Production  curves,  oil  wells,  335,  338,  340,  341,  365. 
Provinces,  petroliferous,  199,  205,  215. 
Pycnometer,  Johnston  and  Adams,  473. 

Red  Beds,  gypsum  origin,  274. 

Refining,  oil,  method,  512. 

REGER,  DAVID  B. :  Carbon  Ratios  of  Coals  in  West  Virginia  Oil  Fields,  522. 

Discussion  on  Genetic  Problems  Affecting  Search  for  New  Oil  Regions,  196,  197 
Regulations,  oil  and  gas  property  taxation,  374. 
Representation,  employees',  Standard  Oil  Co.,  237. 
REQUA,  M.  L.:  Discussions:  on  A  Foreign  Oil  Supply  for  the  United  States,  93. 

on  Variation  in  Decline  Curves  of  Various  Oil  Pools,  370. 
Resume  of  Pennsylvania-New  York  Oil  Field  (JOHNSON  and  HUNTLEY,)  151;  Discussion: 

(ASHLEY),  154. 
Rise  and  Decline  in  Production  of  Petroleum  in  Ohio  and  Indiana  (BOWNOCKER),  108; 

Discussion:  (PANYITY),  119. 

Rock  Classification  from  the  Oil-driller's  Standpoint  (KNAPP),  424. 7 
Rogers'  hypothesis,  origin  of  salt  domes,  297. 
Russia:  geology  of  oil  fields,  21. 

oil,  production,  33,  37. 

oil  fields,  see  Oil  fields,  Russia. 

SADTLER,  SAMUEL  P.:  Discussion  on  Composition  of  Petroleum  and  its  Relation  to 

Industrial  Use,  518. 
ST.  CLAIR,  STUART:  Irvine  Oil  District,  Kentucky,  165. 

Discussion  on  Oil  Fields  of  Kentucky  and  Tennessee,  137. 
St.  Louis  meeting,  1920,  proceedings,  vii. 
Salt  cores:  limestone  caps,  274. 

origin,  270,  285. 

origin  of  gypsum,  272,  285. 
Salt  deposits,  bedded,  Gulf  coastal  plain,  298. 
Salt  domes:  European,  303. 

Gulf  coastal  plain:  analogies  with  European  domes,  303. 
oil  accumulation,  319. 


590  INDEX 

Salt  domes:  Gulf  coastal  plain:  origin:  alteration  of  limestone  to  gypsum,  315. 
deposits  underlying,  298. 
forces  producing  intrusion,  302. 
formation  of  domal  materials,  307. 
gas  supply,  310. 
intrusive,  297. 

movement  and  uplift,  317,  318. 
Rogers'  hypothesis,  297. 
salt  and  limestone  supply,  311. 
secondary  deposition,  306. 
secondary  intrusive,  295,  307,  320. 
special  characteristics,  304. 
theories,  284,  295. 

Salta-Jujuy  oil  district,  Argentina,  41. 
Sao  Paulo,  Brazil,  oil-shale,  74. 

SCHUBERT,  CHARLES:  Discussion  on  Petroliferous  Provinces,  204. 
Scotch  oil-shales,  treatment,  233. 
Scotland,  oil,  5. 

Search  for  new  oil  regions,  genetic  problems,  176. 

SEARS,  MORTIMER  A. :  Discussion  on  Oil  Fields  of  Kentucky  and  Tennessee,  133. 
Secondary  Intrusive  Origin  of  Gulf  Coastal  Plain  Salt  Domes  (MATTESON),  295;]Z)is- 
cussion:  (CosTE),  322;  (SHAW),  323;  (POGUE),  324;  (CLAPP),  324;  (DE- 
GOLYER),  325;  (MATTESON),  327,  331;  (HEXON),  329;  (MILLS),  329. 
Segregation  of  oil  above  water,  279. 

SEMMES,  DOUGLAS  R.:  Oil  Possibilities  in  Northern  Alabama,  140. 
Serra  da  Baliza,  petroliferous  rocks,  241. 
Shale,  oil  see  Oil-shale. 
SHAW,  E.  W. :  Discussions:  on  Secondary  Intrusive  Origin  of  Gulf  Coastal  Plain  Salt 

Domes,  323. 

on  Water  Displacement  in  Oil  and  Gas  Sands,  502. 
SHIDEL,  H.  R.,  McCoy,  ALEX.  W.,  and  TRACER,  E.  A.:  Investigations  Concerning 

Oil-water  Emulsion,  430. 
SINGEWALD,  J.  T.,  JR.:  Discussion  on  Carbon  Ratios  of  Coals  in  West  Virginia  Oil 

Fields,  526. 

SMALL,  W.  M.:  Discussion  on  Determination  of  Pore  Space  of  Oil  and  Gas  Sands,  490. 
SMITH,  GEORGE  OTIS:  A  Foreign  Oil  Supply  for  the  United  States,  89. 
SMITH,  R.  A.:  Discussion  on  Value  of  American  Oil-shales,  236. 
SMITH,  WARREN  Du  PRE:  Petroleum  in  the  Philippines,  47. 
Solubility:  calcium  bicarbonate  in  sodium  chloride  solutions,  275. 

calcium  sulfate  in  sodium  chloride  solutions,  273. 
Speculation,  oil  fields,  353. 
Standard  Oil  Co.:  conferences,  works,  238. 
industrial  representation,  237. 
insurance,  employees',  240. 
labor  policy,  237. 
Substitutes,  oil,  83. 
Sulfur,  in  petroleum,  509. 

Tank  steamers,  Mexican  petroleum,  535 
Taxation:  Mexico,  controversies,  557. 

oil:  Mexico,  see  Oil,  Mexico,  taxation 
relation  with  oil-coal  price,  555. 

oil  and  gas  properties:  accounts,  375. 


INDEX  591 

Taxation:  oil  and  gas  properties:  ad  valorem  basis,  393. 
allowances,  375,  378,  387. 
capital  invested,  379. 
capital  sum,  381. 
.  depletion,  382. 
depreciation,  387. 
invested  capital,  379. 
items  not  deductible,  391. 
proof  of  discovery,  378. 

quantity  of  oil  in  ground,  determination,  381. 
records,  392. 

recoverable  reserves,  382. 
regulations,  374. 
revaluation,  377. 

surplus  and  undivided  profits,  379. 
Treasury  Department  Manual,  suggestions,  387,  388. 
valuation,  376. 
Tennessee,  oil  fields,  122. 

THIESSEN,  REINHARDT:  Discussion  on  Nature  of  Coal,  224. 

THOMAS,  J.  ELMER:  Discussion  on  Oil-shales  and  Petroleum  Prospects  in  Brazil,  76. 
THOMPSON,  A.  BEEBY:  Discussion  on  Oil  Fields  of  Russia,  38. 
THOMPSON,  A.  BEEBY  and  MADGWICK,  T.  G. :  Oil  Fields  of  Russia,  17. 
TILLSON,  B.  F.:  Discussion  on  Composition  of  Petroleum  and  its  Relation  to  Industrial 

Use,  520. 
TRACER,  E.  A.:  Discussions:  on  Investigations  Concerning  Oil-water  Emulsion,  454, 

455,  456,  457. 

OTi  Value  of  American  Oil-shales,  234,  235. 
TRACER,  E.  A.,  McCoY,  ALEX.  W.,  and  SHIDEL,  H.  R.:  Investigations  Concerning 

Oil-water  Emulsion,  430. 

Treasury  Department  Manual,  oil  and  gas  property  taxation,  387,  388. 
Trenton  limestone,  Ohio  and  Indiana,  petroleum,  109. 
Trinidad:  geologic  column,  65. 
map,  oil  fields,  59. 
oil  fields,  58. 
oil  occurrence,  61. 
stratigraphy,  60,  65. 

Units,  measurements,  Mexico,  531. 
Use:  gasoline,  513. 
lubricants,  514. 

Valuation,  oil  properties:  amortization,  350. 
barrel-day  values,  412. 
costs,  348. 

depletion  curves,  405,  409. 
drilling  program,  346. 
establishment  for  taxation,  376. 
factors,  344,  359. 
future  expectation,  345. 
future  price  of  oil,  347. 
interest  on  investment,  349. 
land  classification,  346. 
method,  356. 
"paying  out,"  412. 


592  INDEX 

Valuation,  rate  of  production,  345. 

salvage  value  of  equipment,  352. 

Valuation  Factors  of  Casing-head  Gas  Industry  (BRADLEY),  395. 
Value,  oil  fields,  353,  355. 
Value  of  American  Oil-shales  (BASKERVILLE),  229;  Discussion:  (PEARSE),  233;  (TRA- 

GER),  234,  235;  (WASHBURNE),  234,  235;  (AMBROSE),  235;  (SMITH),  236. 
Variation  in  Decline  Curves  of  Various  Oil  Pools  (JOHNSON),  365;  Discussion:  (REQUA), 

370;  (WASHBURNE),  370;  (BEAL),  370;  (JOHNSON),  373;  (ARNOLD),  373. 
VEATCH,  A.  C. :  Petroleum  Resources  of  Great  Britain,  3. 
Viscosity,  lubricants,  relation  to  quality,  520,  521. 

WALDO,  LEONARD:  Discussion  on  International  Aspects  of  the  Petroleum,  Industry,  87. 
WASHBURNE,  CHESTER  W.:  Oil-field  Brines,  269;  Discussion,  290. 

Discussions:  on  Determination  of  Pore  Space  of  Oil  and  Gas  Sands,  497. 
on  A  Foreign  Oil  Supply  for  the  United  States,  94. 
on  Investigations  Concerning  Oil-water  Emulsion,  455,  457. 
on  Petroleum  Resources  of  Great  Britain,  6. 
on  Petroliferous  Provinces,  216. 
on  Value  of  American  Oil-shales,  234,  235. 
on  Variation  in  Decline  Curves  of  Various  Oil  Pools,  370. 

Water  Displacement  in  Oil  and  Gas  Sands  (JOHNSON),  498;  Discussion:  (WHITE),  501, 
504;  (ASHLEY),  501,  502;  (PAIGE),  501,  502;  (JOHNSON),  502,  503;  (SHAW), 
502;  (HIXON),  503. 

Water  invasion,  oil  wells:  analysis  of  water,  253. 
bottom,  263,  265. 
correction,  262. 
detectors,  256. 
edge  water,  264. 
effect  on  production,  246. 
field  tests,  252. 
indications,  258. 
intermediate,  263. 
maps  and  cross-sections,  249. 
objections,  246. 
sources,  246,  259,  267. 
top  water,  262. 

Water-oil  emulsion,  see  Oil-water  emulsion. 
WATERS,  C.  E.:  Discussion  on  Nature  of  Coal,  227. 
Well  logs:  interpretation,  424. 

rock  types,  424. 
West  Virginia:  coal,  carbon  ratios,  522,  525. 

map,  isocarb  lines  and  oil  and  gas  areas,  523. 
oil,  limits,  524. 
oil  and  gas  areas,  523. 

WHITE,  DAVID:  Genetic  Problems  Affecting  Search  for  New  Oil  Regions,  176. 
Discussions:  on  Nature  of  Coal,  223. 
on  Oil  Fields  of  Persia,  16. 
on  Oil  Possibilities  in  Northern  Alabama,  150. 
on  Oil-shales  and  Petroleum  Prospects  in  Brazil,  76. 
on  Petroleum  in  the  Philippines,  56. 
on  Water  Displacement  in  Oil  and  Gas  Sands,  501,  504. 
WILLIAMS,  HORACE  E.:  Oil-shales  and  Petroleum  Prospects  in  Brazil,  69. 
WOODRUFF,  E.  G. :  Petroliferous  Provinces,  199. 


